chem_section_10.3_powerpoint.ppt
•Download as PPT, PDF•
0 likes•6 views
This document discusses electronegativity and how it can be used to determine the polarity of bonds and molecules. It explains that electronegativity increases moving left to right across a period and decreases down a group on the periodic table. Bonds between atoms with an electronegativity difference of 0 to 0.4 are nonpolar, while those with a difference of 0.5 to 1.7 are polar covalent. Molecules are nonpolar if the polar bonds cancel out, and polar if the bond dipoles do not cancel out. Determining polarity involves considering bond polarity and molecular geometry.
Report
Share
Report
Share
Recommended
COVALENT BOND.pdf
This document discusses covalent bonding. Covalent bonding involves the sharing of electron pairs between atoms. There are two types of covalent bonds: polar covalent bonds, which involve unequal sharing of electrons between atoms with different electronegativities, and nonpolar covalent bonds, which involve equal sharing of electrons between atoms of similar electronegativity. The document provides steps for identifying if a covalent bond is polar or nonpolar based on the electronegativity difference between the atoms.
Polar Bonds and Polar Molecules.pptx
This document discusses molecular polarity and how to determine if molecules are polar or nonpolar. It defines polar and nonpolar covalent bonds based on differences in electronegativity between atoms. A molecule is polar if it contains polar bonds in an asymmetrical arrangement, whereas a molecule is nonpolar if the polar bonds are symmetrical or if all bonds are nonpolar. Examples of polar molecules include HCl and H2O, while nonpolar examples include CO2 and CF4.
CH6_7_Electronegativity_and_Bond_Polarity_GOB_Structures_5th_ed.pptx
The document discusses electronegativity and how it is used to determine bond polarity. It states that electronegativity increases across periods and up groups in the periodic table. Bond polarity is predicted by the difference in electronegativity values - a difference of 0-0.4 results in a nonpolar covalent bond, 0.5-1.8 in a polar covalent bond, and over 1.8 in an ionic bond. Examples of various bond types are given based on the electronegativity difference between atoms.
Protein_Basics.pptx
The document discusses the properties of amino acids. It explains that amino acids can be hydrophobic, hydrophilic, or amphipathic based on their hydropathy index. Amphipathic amino acids are beneficial because they can tolerate changes in environment between hydrophilic and hydrophobic. The document also discusses the differences between ampholytes and amphoteric molecules, and explains concepts like electronegativity, dipole moments, and dielectric constants in the context of amino acid properties.
02thechemicalcontextoflife 130311053231-phpapp01
1) Matter is composed of chemical elements and their combinations called compounds. Elements consist of unique atoms that are made of subatomic particles like protons, neutrons, and electrons.
2) Chemical bonds, including covalent and ionic bonds, form between atoms and result in molecules with distinct shapes and properties. Covalent bonds are formed by shared electron pairs while ionic bonds involve electron transfers.
3) Chemical reactions make and break bonds to form new molecules. Photosynthesis converts carbon dioxide and water into glucose and oxygen through a key reaction in living systems.
POLARITY OF MOLECULES.pptx
This document provides an overview of molecular polarity. It defines key terms like electronegativity, polar bonds, and molecular polarity. The objectives are to define electronegativity, distinguish between polar and non-polar molecules, and explain how molecular polarity relates to properties like melting points and solubility. Examples of polar molecules like water and non-polar molecules like nitrogen are given. Bond polarity is determined by differences in electronegativity between atoms, while molecular polarity depends on both bond polarity and molecular geometry.
03_Lecture SK.ppt
This document provides an overview of Chapter 3 from a chemistry textbook on compounds and bonding. It discusses electron arrangements and the octet rule, how atoms gain or lose electrons to form ions and achieve stable electron configurations, and the formation of ionic and covalent compounds through electron transfer or sharing. It also introduces the mole as a unit for counting particles at the atomic scale and methods for determining the number of atoms or molecules in a sample based on its mass in grams. The key topics covered are the octet rule, ion formation, writing formulas for ionic compounds, drawing Lewis structures to represent covalent bonding, and performing stoichiometric calculations using the mole concept.
Electronegativity
This document discusses electronegativity and how it can be used to predict bond polarity. It explains that electronegativity increases across periods and up groups in the periodic table. Bond polarity is determined by the difference in electronegativity between the bonded atoms - a small difference leads to nonpolar covalent bonds, a moderate difference leads to polar covalent bonds, and a large difference leads to ionic bonds through electron transfer. Examples are given of different bond types classified by their electronegativity differences.
Recommended
COVALENT BOND.pdf
This document discusses covalent bonding. Covalent bonding involves the sharing of electron pairs between atoms. There are two types of covalent bonds: polar covalent bonds, which involve unequal sharing of electrons between atoms with different electronegativities, and nonpolar covalent bonds, which involve equal sharing of electrons between atoms of similar electronegativity. The document provides steps for identifying if a covalent bond is polar or nonpolar based on the electronegativity difference between the atoms.
Polar Bonds and Polar Molecules.pptx
This document discusses molecular polarity and how to determine if molecules are polar or nonpolar. It defines polar and nonpolar covalent bonds based on differences in electronegativity between atoms. A molecule is polar if it contains polar bonds in an asymmetrical arrangement, whereas a molecule is nonpolar if the polar bonds are symmetrical or if all bonds are nonpolar. Examples of polar molecules include HCl and H2O, while nonpolar examples include CO2 and CF4.
CH6_7_Electronegativity_and_Bond_Polarity_GOB_Structures_5th_ed.pptx
The document discusses electronegativity and how it is used to determine bond polarity. It states that electronegativity increases across periods and up groups in the periodic table. Bond polarity is predicted by the difference in electronegativity values - a difference of 0-0.4 results in a nonpolar covalent bond, 0.5-1.8 in a polar covalent bond, and over 1.8 in an ionic bond. Examples of various bond types are given based on the electronegativity difference between atoms.
Protein_Basics.pptx
The document discusses the properties of amino acids. It explains that amino acids can be hydrophobic, hydrophilic, or amphipathic based on their hydropathy index. Amphipathic amino acids are beneficial because they can tolerate changes in environment between hydrophilic and hydrophobic. The document also discusses the differences between ampholytes and amphoteric molecules, and explains concepts like electronegativity, dipole moments, and dielectric constants in the context of amino acid properties.
02thechemicalcontextoflife 130311053231-phpapp01
1) Matter is composed of chemical elements and their combinations called compounds. Elements consist of unique atoms that are made of subatomic particles like protons, neutrons, and electrons.
2) Chemical bonds, including covalent and ionic bonds, form between atoms and result in molecules with distinct shapes and properties. Covalent bonds are formed by shared electron pairs while ionic bonds involve electron transfers.
3) Chemical reactions make and break bonds to form new molecules. Photosynthesis converts carbon dioxide and water into glucose and oxygen through a key reaction in living systems.
POLARITY OF MOLECULES.pptx
This document provides an overview of molecular polarity. It defines key terms like electronegativity, polar bonds, and molecular polarity. The objectives are to define electronegativity, distinguish between polar and non-polar molecules, and explain how molecular polarity relates to properties like melting points and solubility. Examples of polar molecules like water and non-polar molecules like nitrogen are given. Bond polarity is determined by differences in electronegativity between atoms, while molecular polarity depends on both bond polarity and molecular geometry.
03_Lecture SK.ppt
This document provides an overview of Chapter 3 from a chemistry textbook on compounds and bonding. It discusses electron arrangements and the octet rule, how atoms gain or lose electrons to form ions and achieve stable electron configurations, and the formation of ionic and covalent compounds through electron transfer or sharing. It also introduces the mole as a unit for counting particles at the atomic scale and methods for determining the number of atoms or molecules in a sample based on its mass in grams. The key topics covered are the octet rule, ion formation, writing formulas for ionic compounds, drawing Lewis structures to represent covalent bonding, and performing stoichiometric calculations using the mole concept.
Electronegativity
This document discusses electronegativity and how it can be used to predict bond polarity. It explains that electronegativity increases across periods and up groups in the periodic table. Bond polarity is determined by the difference in electronegativity between the bonded atoms - a small difference leads to nonpolar covalent bonds, a moderate difference leads to polar covalent bonds, and a large difference leads to ionic bonds through electron transfer. Examples are given of different bond types classified by their electronegativity differences.
Electronegativity.pptx
This document discusses electronegativity and how it can be used to predict bond polarity. It explains that electronegativity increases across periods and up groups in the periodic table. Bond polarity is determined by the difference in electronegativity between the bonded atoms - a small difference leads to nonpolar covalent bonds, a moderate difference leads to polar covalent bonds, and a large difference leads to ionic bonds through electron transfer. Examples are given of different bond types classified by their electronegativity differences.
Covalent Bond.pptx
Covalent bond, in chemistry, the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons. A covalent bond forms when the bonded atoms have a lower total energy than that of widely separated atoms. A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms. These electrons are simultaneously attracted by the two atomic nuclei. A covalent bond forms when the difference between the electronegativities of two atoms is too small for an electron transfer to occur to form ions.
Polarity and Intermolecular forces
The document discusses different types of chemical bonds including polar and nonpolar bonds. It explains that polarity refers to differences in electronegativity between atoms in a bond. Polar bonds form when electrons are shared unequally, resulting in partial positive and negative charges on different parts of the molecule. Nonpolar bonds share electrons equally. The document also describes properties influenced by bond polarity like boiling point and solubility. It discusses hydrogen bonding, ionic bonding, and van der Waals forces as types of intermolecular forces.
Physical Science: POLARITY OF MOLECULES.pptx
This document discusses the polarity of molecules. It defines polarity and explains that the two main factors that determine molecular polarity are: 1) the polarity of bonds between atoms, which is determined by electronegativity, and 2) the geometric shape of the molecule, which can be predicted using VSEPR theory. It also differentiates between polar and nonpolar covalent bonds and molecules based on electronegativity differences and molecular geometry. Examples of polar and nonpolar molecules are provided.
Physical Science: POLARITY OF MOLECULES.pptx
This document discusses the polarity of molecules. It defines polarity and explains that the two main factors that determine molecular polarity are: 1) the polarity of bonds between atoms, which is determined by electronegativity, and 2) the geometric shape of the molecule, which can be predicted using VSEPR theory. It also differentiates between polar and nonpolar covalent bonds and molecules based on electronegativity differences and molecular geometry. Examples of polar and nonpolar molecules are provided.
09 lecture
This document summarizes key concepts from Chapter 9 of Chemistry: A Molecular Approach, 2nd Ed. by Nivaldo Tro, including:
- Lewis bonding theory uses valence electrons to explain how atoms bond by transferring or sharing electrons to achieve stable electron configurations like noble gases.
- Ionic bonds form when a metal transfers valence electrons to a nonmetal, creating oppositely charged ions that are attracted in a crystal lattice.
- Covalent bonds form when nonmetals share valence electrons to achieve stable configurations.
- The octet rule and Lewis dot structures can predict molecular geometry and polarity.
- Lattice energy released in crystal formation explains why ionic compounds are more stable than separate ions.
Types of Chemical Bonds
This document discusses different types of chemical bonds including covalent bonds, ionic bonds, metallic bonds, and hydrogen bonds. It explains that a chemical bond is an attraction between atoms that allows the formation of compounds. Covalent bonds involve the sharing of electron pairs between atoms, while ionic bonds involve the complete transfer of electrons from one atom to another, resulting in positively and negatively charged ions. The document also discusses electronegativity and how differences in electronegativity between bonded atoms determine whether a bond is polar or nonpolar. Polar bonds result in partial charges on atoms and a dipole moment, while nonpolar bonds do not.
IM forces.pptx
1. The document discusses molecular shapes and intermolecular forces. It explains that molecular shape is determined by valence shell electron pair repulsion (VSEPR) theory, where electron pairs around an atom repel each other and take up positions as far apart as possible.
2. The most common molecular shapes are linear, trigonal planar, tetrahedral, trigonal pyramidal, and bent. Molecular polarity depends on bond polarity and symmetry. Polar molecules have an uneven distribution of charge while nonpolar molecules have symmetrical charge distributions.
3. Intermolecular forces include hydrogen bonding, dipole-dipole interactions, and dispersion forces. Hydrogen bonding is the strongest and occurs between molecules with hydrogen bonded to fluorine,
Lesson 8 physical science
This document discusses intermolecular forces and polarity. It defines intermolecular forces as the attractive or repulsive forces between molecules. The document then explains the different types of intermolecular forces and how they relate to a substance's properties. It also discusses how intermolecular forces are used in applications like medical implants and electronics. Next, it describes how polarity is determined by bond polarity and molecular geometry. Polar molecules interact through dipole-dipole interactions and hydrogen bonding, while non-polar molecules interact through London dispersion forces. The document provides several examples of applying concepts of electronegativity, bond polarity, and molecular geometry to determine if a substance is polar or non-polar.
johnvic098 chemical bonds inoin bond covalent bond metallic bond.pptx
Ionic bonds form when electrons are transferred permanently from one atom to another, resulting in oppositely charged ions that are attracted to each other. The atom that loses electrons becomes a positively charged cation, while the atom that gains electrons becomes a negatively charged anion. Ionic bonds form crystalline solids where the ions are arranged so that positive and negative charges alternate, balancing each other out and resulting in an overall neutral charge. Ionic crystals have considerable electrostatic forces, making them hard and nonvolatile.
Electronegativity
The electronegativity of an element is a measure of how strongly it attracts electrons in a covalent bond. Electronegativity increases left to right and top to bottom in a period, and metals have the lowest values while nonmetals have the highest. The difference in electronegativity between two bonded atoms indicates bond type - ionic bonds form when difference is >1.7, covalent bonds form when difference is <1.7, and polar covalent bonds form for differences in between. Electronegativity values can be used to predict and investigate bond types.
The atom
The electronegativity of an element is a measure of how strongly it attracts electrons in a covalent bond. Electronegativity increases left to right and top to bottom in a period, and metals have the lowest values while nonmetals have the highest. The difference in electronegativity between two bonded atoms indicates bond type - ionic bonds form when difference is >1.7, covalent bonds form when difference is <1.7, and polar covalent bonds form for differences in between. Electronegativity values can be used to predict and investigate bond types.
electronegativity in molecules covalent bonding
The document discusses electronegativity and how it relates to bond polarity. Electronegativity is a measure of an atom's attraction for electrons, and differences in electronegativity between atoms determine if a bond is polar or nonpolar. Polar covalent bonds form when atoms pull electrons unequally, resulting in partial charges. Whether a molecule is polar depends on both bond polarity and molecular symmetry. The properties of covalent compounds, such as their relatively low melting/boiling points, result from weak intermolecular forces like van der Waals forces, dipole-dipole interactions, and hydrogen bonding.
Q1_WK3_L4_PHYSCI_ELECTRONEGATIVITY.pptx
The document discusses electronegativity and how it can be used to predict bond polarity and type. Electronegativity is an atom's ability to attract shared electrons in a bond. The difference in electronegativity values between two bonded atoms determines whether the bond is nonpolar covalent, polar covalent, or ionic. A difference of 0-0.4 results in a nonpolar covalent bond, 0.5-1.8 in a polar covalent bond, and over 1.8 in an ionic bond. Examples of various bonds are given along with their electronegativity differences and bond types.
Physical Science Week 2.1.pptx
This document provides an overview of molecular polarity. It defines key terms like electronegativity, polar bonds, and non-polar bonds. It explains how the polarity of molecules is determined by two main factors: 1) the polarity of the bonds between atoms as determined by electronegativity differences, and 2) the geometrical shape of the molecule as predicted by VSEPR theory. Examples of polar and non-polar molecules are given to illustrate how molecular polarity relates to bond polarity and molecular geometry.
4 converted (1)
This document provides an introduction to hydrocarbons, which are organic compounds composed of hydrogen and carbon. It discusses the characteristics of hydrocarbons and defines different types including aliphatic hydrocarbons (alkanes, alkenes, alkynes), aromatic hydrocarbons, and introduces chemical bonding concepts like ionic bonds, covalent bonds, and coordinate covalent bonds. It provides examples and properties of different hydrocarbon groups and bond types.
Determine whether the bond between each of the following pairs of atom.docx
Determine whether the bond between each of the following pairs of atoms is purely covalent, polar covalent, or ionic.
1. O and O
2. Li and O
3. C and N
4. N and S
Solution
Pure covalent bond- when both the participating atoms are having same electronegativity value (i.e- for homonuclear molecules) Exp - O and O
polar covalent bond- both particiapting atoms share equal number of electrons to form coavalent bond, however, the shared electron pair remains more towards the more electronegative atoms.
Exp- C and N (electronegativity of N is more than C, the share electron pair remains towards the nitrogen. carbon bears partial positive charge and nitrogen bears partial negative charge)
N and S (electronegativity of N is more than S, the share electron pair remains towards the nitrogen. sulfur bears partial positive charge and nitrogen bears partial negative charge)
Ionic bond - one atom is highly electronegative and the other atom is highly electropositive
EXp- Li and O
.
09 polarity 2016
This document discusses molecular shape and polarity. It explains that polarity depends on polar bonds and molecular symmetry. A polar molecule has polar bonds whose dipoles do not cancel out, while a nonpolar molecule has either nonpolar bonds or polar bonds whose dipoles cancel out. It provides steps to determine polarity: draw Lewis structures, use VSEPR to predict shape, determine bond polarity from electronegativity differences, and add bond dipoles. Symmetric molecules with identical bonds are nonpolar as the dipoles cancel. Asymmetric molecules or those with different bond polarities, like NH3, are polar.
Tang 08 polarity
This document discusses molecular shape and polarity. It explains that a molecule's polarity depends on the presence of polar bonds and its overall shape. Polar bonds form when there is an unequal sharing of electrons between atoms. To determine a molecule's polarity, one must draw its Lewis structure, use VSEPR theory to predict its shape, determine if bonds are polar, then add bond dipoles. If dipoles cancel out, the molecule is nonpolar. If not, it is polar. Symmetry is also important - symmetrical molecules with identical bond polarities are nonpolar. Examples include the polar NH3 and nonpolar CO2 and symmetrical NF3.
Polarity.pptx
The document discusses molecular polarity and geometry. It defines electronegativity as a measure of an atom's ability to attract electrons. Polar bonds form when there is a large difference in electronegativity between atoms. Molecular geometry can be determined using VSEPR theory by counting bonding pairs and lone pairs around the central atom. The shape that minimizes electron repulsion is the molecular geometry. Solubility and miscibility are related to polarity - like dissolves like, so polar substances mix with each other but not with nonpolar substances.
Facism-Anarchism-by-Group-2-PolGov (1).pptx
This document provides an overview of fascism and anarchism. It defines fascism as an authoritarian right-wing ideology emphasizing nationalism and state power. Fascism originated in Italy after World War 1 under Mussolini. Key characteristics include militarism, nationalism, corporatism, and suppression of opposition. The document also discusses prominent fascist leaders like Hitler, Franco, and aspects of fascism in the Philippines under Marcos. Anarchism is defined as a philosophy seeking to abolish unjust hierarchies and the state. It originated in ancient times but grew in the 19th century. Key anarchist principles are outlined, as well as prominent figures and its history in the Philippines. Differences between fascism and anarchism are contrasted.
light lesson sfdgdfhhghggdwqeseqwwrewrre
Light can be described as both a wave and a particle. Early theories viewed light as a stream of particles, while later wave theories described light as an electromagnetic wave. Modern physics reconciles both views by explaining that light consists of discrete packets of energy called photons that exhibit both wave-like and particle-like properties. The photon's energy is directly proportional to the electromagnetic wave's frequency.
More Related Content
Similar to chem_section_10.3_powerpoint.ppt
Electronegativity.pptx
This document discusses electronegativity and how it can be used to predict bond polarity. It explains that electronegativity increases across periods and up groups in the periodic table. Bond polarity is determined by the difference in electronegativity between the bonded atoms - a small difference leads to nonpolar covalent bonds, a moderate difference leads to polar covalent bonds, and a large difference leads to ionic bonds through electron transfer. Examples are given of different bond types classified by their electronegativity differences.
Covalent Bond.pptx
Covalent bond, in chemistry, the interatomic linkage that results from the sharing of an electron pair between two atoms. The binding arises from the electrostatic attraction of their nuclei for the same electrons. A covalent bond forms when the bonded atoms have a lower total energy than that of widely separated atoms. A covalent bond consists of the mutual sharing of one or more pairs of electrons between two atoms. These electrons are simultaneously attracted by the two atomic nuclei. A covalent bond forms when the difference between the electronegativities of two atoms is too small for an electron transfer to occur to form ions.
Polarity and Intermolecular forces
The document discusses different types of chemical bonds including polar and nonpolar bonds. It explains that polarity refers to differences in electronegativity between atoms in a bond. Polar bonds form when electrons are shared unequally, resulting in partial positive and negative charges on different parts of the molecule. Nonpolar bonds share electrons equally. The document also describes properties influenced by bond polarity like boiling point and solubility. It discusses hydrogen bonding, ionic bonding, and van der Waals forces as types of intermolecular forces.
Physical Science: POLARITY OF MOLECULES.pptx
This document discusses the polarity of molecules. It defines polarity and explains that the two main factors that determine molecular polarity are: 1) the polarity of bonds between atoms, which is determined by electronegativity, and 2) the geometric shape of the molecule, which can be predicted using VSEPR theory. It also differentiates between polar and nonpolar covalent bonds and molecules based on electronegativity differences and molecular geometry. Examples of polar and nonpolar molecules are provided.
Physical Science: POLARITY OF MOLECULES.pptx
This document discusses the polarity of molecules. It defines polarity and explains that the two main factors that determine molecular polarity are: 1) the polarity of bonds between atoms, which is determined by electronegativity, and 2) the geometric shape of the molecule, which can be predicted using VSEPR theory. It also differentiates between polar and nonpolar covalent bonds and molecules based on electronegativity differences and molecular geometry. Examples of polar and nonpolar molecules are provided.
09 lecture
This document summarizes key concepts from Chapter 9 of Chemistry: A Molecular Approach, 2nd Ed. by Nivaldo Tro, including:
- Lewis bonding theory uses valence electrons to explain how atoms bond by transferring or sharing electrons to achieve stable electron configurations like noble gases.
- Ionic bonds form when a metal transfers valence electrons to a nonmetal, creating oppositely charged ions that are attracted in a crystal lattice.
- Covalent bonds form when nonmetals share valence electrons to achieve stable configurations.
- The octet rule and Lewis dot structures can predict molecular geometry and polarity.
- Lattice energy released in crystal formation explains why ionic compounds are more stable than separate ions.
Types of Chemical Bonds
This document discusses different types of chemical bonds including covalent bonds, ionic bonds, metallic bonds, and hydrogen bonds. It explains that a chemical bond is an attraction between atoms that allows the formation of compounds. Covalent bonds involve the sharing of electron pairs between atoms, while ionic bonds involve the complete transfer of electrons from one atom to another, resulting in positively and negatively charged ions. The document also discusses electronegativity and how differences in electronegativity between bonded atoms determine whether a bond is polar or nonpolar. Polar bonds result in partial charges on atoms and a dipole moment, while nonpolar bonds do not.
IM forces.pptx
1. The document discusses molecular shapes and intermolecular forces. It explains that molecular shape is determined by valence shell electron pair repulsion (VSEPR) theory, where electron pairs around an atom repel each other and take up positions as far apart as possible.
2. The most common molecular shapes are linear, trigonal planar, tetrahedral, trigonal pyramidal, and bent. Molecular polarity depends on bond polarity and symmetry. Polar molecules have an uneven distribution of charge while nonpolar molecules have symmetrical charge distributions.
3. Intermolecular forces include hydrogen bonding, dipole-dipole interactions, and dispersion forces. Hydrogen bonding is the strongest and occurs between molecules with hydrogen bonded to fluorine,
Lesson 8 physical science
This document discusses intermolecular forces and polarity. It defines intermolecular forces as the attractive or repulsive forces between molecules. The document then explains the different types of intermolecular forces and how they relate to a substance's properties. It also discusses how intermolecular forces are used in applications like medical implants and electronics. Next, it describes how polarity is determined by bond polarity and molecular geometry. Polar molecules interact through dipole-dipole interactions and hydrogen bonding, while non-polar molecules interact through London dispersion forces. The document provides several examples of applying concepts of electronegativity, bond polarity, and molecular geometry to determine if a substance is polar or non-polar.
johnvic098 chemical bonds inoin bond covalent bond metallic bond.pptx
Ionic bonds form when electrons are transferred permanently from one atom to another, resulting in oppositely charged ions that are attracted to each other. The atom that loses electrons becomes a positively charged cation, while the atom that gains electrons becomes a negatively charged anion. Ionic bonds form crystalline solids where the ions are arranged so that positive and negative charges alternate, balancing each other out and resulting in an overall neutral charge. Ionic crystals have considerable electrostatic forces, making them hard and nonvolatile.
Electronegativity
The electronegativity of an element is a measure of how strongly it attracts electrons in a covalent bond. Electronegativity increases left to right and top to bottom in a period, and metals have the lowest values while nonmetals have the highest. The difference in electronegativity between two bonded atoms indicates bond type - ionic bonds form when difference is >1.7, covalent bonds form when difference is <1.7, and polar covalent bonds form for differences in between. Electronegativity values can be used to predict and investigate bond types.
The atom
The electronegativity of an element is a measure of how strongly it attracts electrons in a covalent bond. Electronegativity increases left to right and top to bottom in a period, and metals have the lowest values while nonmetals have the highest. The difference in electronegativity between two bonded atoms indicates bond type - ionic bonds form when difference is >1.7, covalent bonds form when difference is <1.7, and polar covalent bonds form for differences in between. Electronegativity values can be used to predict and investigate bond types.
electronegativity in molecules covalent bonding
The document discusses electronegativity and how it relates to bond polarity. Electronegativity is a measure of an atom's attraction for electrons, and differences in electronegativity between atoms determine if a bond is polar or nonpolar. Polar covalent bonds form when atoms pull electrons unequally, resulting in partial charges. Whether a molecule is polar depends on both bond polarity and molecular symmetry. The properties of covalent compounds, such as their relatively low melting/boiling points, result from weak intermolecular forces like van der Waals forces, dipole-dipole interactions, and hydrogen bonding.
Q1_WK3_L4_PHYSCI_ELECTRONEGATIVITY.pptx
The document discusses electronegativity and how it can be used to predict bond polarity and type. Electronegativity is an atom's ability to attract shared electrons in a bond. The difference in electronegativity values between two bonded atoms determines whether the bond is nonpolar covalent, polar covalent, or ionic. A difference of 0-0.4 results in a nonpolar covalent bond, 0.5-1.8 in a polar covalent bond, and over 1.8 in an ionic bond. Examples of various bonds are given along with their electronegativity differences and bond types.
Physical Science Week 2.1.pptx
This document provides an overview of molecular polarity. It defines key terms like electronegativity, polar bonds, and non-polar bonds. It explains how the polarity of molecules is determined by two main factors: 1) the polarity of the bonds between atoms as determined by electronegativity differences, and 2) the geometrical shape of the molecule as predicted by VSEPR theory. Examples of polar and non-polar molecules are given to illustrate how molecular polarity relates to bond polarity and molecular geometry.
4 converted (1)
This document provides an introduction to hydrocarbons, which are organic compounds composed of hydrogen and carbon. It discusses the characteristics of hydrocarbons and defines different types including aliphatic hydrocarbons (alkanes, alkenes, alkynes), aromatic hydrocarbons, and introduces chemical bonding concepts like ionic bonds, covalent bonds, and coordinate covalent bonds. It provides examples and properties of different hydrocarbon groups and bond types.
Determine whether the bond between each of the following pairs of atom.docx
Determine whether the bond between each of the following pairs of atoms is purely covalent, polar covalent, or ionic.
1. O and O
2. Li and O
3. C and N
4. N and S
Solution
Pure covalent bond- when both the participating atoms are having same electronegativity value (i.e- for homonuclear molecules) Exp - O and O
polar covalent bond- both particiapting atoms share equal number of electrons to form coavalent bond, however, the shared electron pair remains more towards the more electronegative atoms.
Exp- C and N (electronegativity of N is more than C, the share electron pair remains towards the nitrogen. carbon bears partial positive charge and nitrogen bears partial negative charge)
N and S (electronegativity of N is more than S, the share electron pair remains towards the nitrogen. sulfur bears partial positive charge and nitrogen bears partial negative charge)
Ionic bond - one atom is highly electronegative and the other atom is highly electropositive
EXp- Li and O
.
09 polarity 2016
This document discusses molecular shape and polarity. It explains that polarity depends on polar bonds and molecular symmetry. A polar molecule has polar bonds whose dipoles do not cancel out, while a nonpolar molecule has either nonpolar bonds or polar bonds whose dipoles cancel out. It provides steps to determine polarity: draw Lewis structures, use VSEPR to predict shape, determine bond polarity from electronegativity differences, and add bond dipoles. Symmetric molecules with identical bonds are nonpolar as the dipoles cancel. Asymmetric molecules or those with different bond polarities, like NH3, are polar.
Tang 08 polarity
This document discusses molecular shape and polarity. It explains that a molecule's polarity depends on the presence of polar bonds and its overall shape. Polar bonds form when there is an unequal sharing of electrons between atoms. To determine a molecule's polarity, one must draw its Lewis structure, use VSEPR theory to predict its shape, determine if bonds are polar, then add bond dipoles. If dipoles cancel out, the molecule is nonpolar. If not, it is polar. Symmetry is also important - symmetrical molecules with identical bond polarities are nonpolar. Examples include the polar NH3 and nonpolar CO2 and symmetrical NF3.
Polarity.pptx
The document discusses molecular polarity and geometry. It defines electronegativity as a measure of an atom's ability to attract electrons. Polar bonds form when there is a large difference in electronegativity between atoms. Molecular geometry can be determined using VSEPR theory by counting bonding pairs and lone pairs around the central atom. The shape that minimizes electron repulsion is the molecular geometry. Solubility and miscibility are related to polarity - like dissolves like, so polar substances mix with each other but not with nonpolar substances.
Similar to chem_section_10.3_powerpoint.ppt (20)
johnvic098 chemical bonds inoin bond covalent bond metallic bond.pptx
johnvic098 chemical bonds inoin bond covalent bond metallic bond.pptx
Determine whether the bond between each of the following pairs of atom.docx
Determine whether the bond between each of the following pairs of atom.docx
More from carlmanaay
Facism-Anarchism-by-Group-2-PolGov (1).pptx
This document provides an overview of fascism and anarchism. It defines fascism as an authoritarian right-wing ideology emphasizing nationalism and state power. Fascism originated in Italy after World War 1 under Mussolini. Key characteristics include militarism, nationalism, corporatism, and suppression of opposition. The document also discusses prominent fascist leaders like Hitler, Franco, and aspects of fascism in the Philippines under Marcos. Anarchism is defined as a philosophy seeking to abolish unjust hierarchies and the state. It originated in ancient times but grew in the 19th century. Key anarchist principles are outlined, as well as prominent figures and its history in the Philippines. Differences between fascism and anarchism are contrasted.
light lesson sfdgdfhhghggdwqeseqwwrewrre
Light can be described as both a wave and a particle. Early theories viewed light as a stream of particles, while later wave theories described light as an electromagnetic wave. Modern physics reconciles both views by explaining that light consists of discrete packets of energy called photons that exhibit both wave-like and particle-like properties. The photon's energy is directly proportional to the electromagnetic wave's frequency.
self defense in karatejsbdbbdsbdbdbdbbfb
Karate is a Japanese martial art that focuses on defensive body movements and counterattacks through disciplined training. It originated in Okinawa, Japan and was influenced by Chinese martial arts. Karate practice involves three main components: kihon (basics/fundamentals), kata (predefined patterns of movements), and kumite (sparring). In addition to physical benefits like strength and coordination, regular karate practice provides mental benefits such as clearer thinking, self-confidence, and composure.
cell & dna.pptx
1. The document provides instructions for accessing PowerPoint lecture slides on FirstClass. It explains how to find and download the slides.
2. It then summarizes a biology lecture on cells and DNA. It describes the key components of cells, including the plasma membrane, cytoplasm, nucleus, and organelles. It compares prokaryotic and eukaryotic cells.
3. The summary explains DNA and RNA structure and how genetic information is passed from DNA to mRNA to proteins through the processes of transcription and translation. This allows cells to synthesize proteins according to instructions in their genes.
rate of rxns.pptx
The document discusses the rate of reaction and factors that affect it. It defines rate of reaction as the change in amount of reactants or products per unit time. The rate depends on several factors:
1) The surface area of solid reactants - Increasing the surface area by reducing particle size increases the rate, as there are more contact points for collisions.
2) Concentration of reactants - Higher concentrations increase the chance of collisions between reactant particles, speeding up the rate.
3) Temperature - Raising the temperature increases the kinetic energy of particles, making successful collisions that overcome the activation energy barrier for reaction more likely.
4) Pressure for gas reactions - Higher pressures increase the rate by squeezing
s15-miller-chap-8a-lecture.ppt
Nucleotides are components of nucleic acids DNA and RNA and have several important cellular functions. They contain a nitrogenous base, a pentose sugar, and one or more phosphate groups. The four major nucleotides that make up DNA contain the bases adenine, guanine, cytosine, and thymine. The four major nucleotides that make up RNA contain adenine, guanine, cytosine, and uracil instead of thymine. Nucleotides are linked together via phosphodiester bonds between the 5' phosphate of one nucleotide and the 3' hydroxyl group of the next, forming the backbones of nucleic acids.
Heavier elements.ppt
Three sentences:
When a star's core is made of iron, it can no longer maintain stability and undergoes core collapse, resulting in a supernova explosion. During this explosion, the extreme temperatures and pressures allow for fusion of iron and heavier elements. Elements heavier than iron are formed through rapid neutron capture during supernova explosions, which produce the isotopes of these elements found on the periodic table.
Ch 9 Lipid2.ppt
This document provides an outline for a lecture on lipids and lipoproteins. It begins by defining key terms related to lipids and lipoproteins and describing the different classes of lipids and lipoproteins, including chylomicrons, VLDL, LDL, and HDL. It then discusses apolipoproteins and their functions. The document outlines the laboratory procedures for determining lipid and lipoprotein levels and interpreting the results. It also discusses the significance of lipids and lipoproteins in conditions like atherosclerosis.
proteins2.pptx
This document discusses protein as a nutrient. It begins by introducing protein and explaining that it is essential for growth, maintenance and repair of tissues in the body. It then discusses the classification, sources and functions of protein. Protein can be classified based on its structure, biological function or composition. Sources of protein include both animal and plant foods. Key functions of protein include growth, cell repair, enzyme production and immune function. The recommended daily allowance of protein is 0.8 grams per kilogram of body weight. Deficiencies can result in diseases like marasmus or kwashiorkor, while excess protein intake has been linked to health issues.
STREETFOODS.pptx
This document presents a research proposal that examines the implications of street food consumption on the health of students at Ramon Avancena National High School. The study will investigate the common street foods eaten by students, potential diseases and illnesses from street foods, and students' awareness of safety issues. Interviews of students will gather data on their street food buying and eating habits, as well as their understanding of advantages and disadvantages related to health. The researchers aim to inform students, teachers, and vendors of potential health impacts to promote hygienic and safe street food practices.
molecular geometry.ppt
VSEPR theory predicts molecular shapes based on electron pair repulsion around a central atom. It assumes that electron pairs will maximize their distance from each other to minimize repulsion. Molecular shapes include tetrahedral, trigonal pyramidal, bent, and linear based on the number of electron pairs. The theory uses Lewis structures to determine electron pairs from bonds and lone pairs, and predicts the shape that minimizes repulsion between these pairs.
Cha2.pptx
Isotope geochemistry can be used for geochronology, understanding solar system and continent evolution, tracing the history of life, unraveling climate history, and determining the origin of mineral and energy resources. The history of isotope geochemistry began with the discovery of radioactivity and production of the first radiometric age for the Earth. Isotopes have differing numbers of neutrons. Nuclear stability depends on the balance of nuclear forces. Radioactive decay follows exponential laws. Isotope ratios are altered by geological processes and can be used to study earth systems. Stable and radioactive isotopes are produced via stellar nucleosynthesis during the lives of stars and their deaths as supernovae.
firemeup.pptx
The document discusses fire hazards and prevention. It defines the elements of the fire triangle as fuel, heat, and oxygen. It identifies various causes of fires such as matches, electrical faults, arson, open flames, fireworks, and static electricity. It provides examples of fuel sources like wood, grass, and kerosene. The document also discusses preventing fires at home through safe practices and what to do in the event of a fire, such as calling emergency services. Safety measures and standard fire safety procedures are emphasized.
RV.pptx
Volcanic eruptions can produce several hazardous events such as pyroclastic flows, lava flows, lahars, ash falls, and noxious gas emissions. Pyroclastic flows are among the most dangerous as they can travel far at high speeds while still hot, burying and burning everything in their path as seen at Pompeii. Lava flows are generally less explosive but can still destroy infrastructure in their path. Lahars, or volcanic mudflows, are deadly as they can flow rapidly while carrying large debris. Volcano monitoring helps observe seismic activity, deformation, and gas outputs to detect signs of impending eruptions and warn of potential hazards.
chap01.ppt
This PowerPoint presentation discusses the process of identifying and correcting hazards. It defines a hazard and explains that the goal of hazard identification is to precisely identify potential harm to workers, equipment, and the environment. The presentation outlines several methods for identifying hazards, such as reviewing injury records, inspecting new processes, and complying with regulations. It also describes how to develop an action plan to address identified hazards through corrective measures, assigned responsibilities, and target dates. Additionally, the presentation explains how to perform a job safety analysis (JSA) by selecting a job, breaking it into steps, identifying potential hazards, and developing solutions.
judiciary.pptx
The Philippine judicial system blends elements of civil law from Spanish influence and common law from American influence. It has a hierarchical structure consisting of lower courts, regional trial courts, appellate courts, specialized courts, and the Supreme Court. In recent decades, reforms have aimed to improve judicial qualifications, independence, accountability, and efficiency. However, issues remain regarding political influence, lack of resources, and case backlogs.
EPPG.pptx
The document traces the evolution of politics and governance in the Philippines from pre-historic times to the present. It discusses the early barangay system ruled by datus, the centralized government established under Spanish colonial rule headed by a governor-general, the revolutionary governments that formed in opposition to Spanish rule led by Aguinaldo, the American colonial period when civil and military governments were established, the creation of the Commonwealth government in 1935 in preparation for independence, the Japanese occupation during World War 2, and provides a list of the 16 presidents of the Philippines since independence.
mitigation.pptx
This document discusses disaster mitigation strategies. It begins by defining disaster management and outlining its objectives. It then distinguishes between structural and non-structural mitigation measures. Structural mitigation involves construction projects to reduce disaster impacts, and includes selecting safe building sites, orienting structures properly, ensuring stability, and building cyclone shelters. Non-structural mitigation seeks to modify human behavior through land use regulations, hazard zoning, and education. The document provides several examples of both structural and non-structural mitigation techniques used in India to reduce disaster risks.
vulnerability in disaster.pptx
This document defines vulnerability and discusses it from different perspectives. Vulnerability refers to the susceptibility of individuals, communities, or systems to harm from hazards. It is determined by physical, social, economic, and environmental factors that influence the ability to prepare for, respond to, and recover from disasters. The document outlines four main types of vulnerability: physical, economic, social, and environmental. Understanding vulnerability is important for assessing disaster risk. Approaches to reducing vulnerability include building codes, insurance, economic diversity, awareness raising, and preparedness measures.
Earthquakes (10).ppt
Logarithmic scales are useful for measuring large ranges of values because they compress large spreads into more even spaces. They align with human perception in fields like sound measurement, where equal ratios in frequency correspond to equal changes in pitch. The Richter scale and Modified Mercalli scale are used to describe earthquake magnitudes and intensities. The Richter scale quantifies seismic energy based on amplitude readings, while the Mercalli scale qualitatively rates observed effects on people and structures on a 12-point scale.
More from carlmanaay (20)
Recently uploaded
Bob Reedy - Nitrate in Texas Groundwater.pdf
Presented at June 6-7 Texas Alliance of Groundwater Districts Business Meeting
bordetella pertussis.................................ppt
Bordettela is a gram negative cocobacilli spread by air born drop let
Thornton ESPP slides UK WW Network 4_6_24.pdf
ESPP presentation to EU Waste Water Network, 4th June 2024 “EU policies driving nutrient removal and recycling
and the revised UWWTD (Urban Waste Water Treatment Directive)”
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Nucleophilic Addition of carbonyl compounds.pptx
Nucleophilic addition is the most important reaction of carbonyls. Not just aldehydes and ketones, but also carboxylic acid derivatives in general.
Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
Neutral nucleophiles can also add to carbonyls, although their additions are generally slower and more reversible. Acid catalysis is sometimes employed to increase the rate of addition.
SAR of Medicinal Chemistry 1st by dk.pdf
In this presentation include the prototype drug SAR on thus or with their examples .
Syllabus of Second Year B. Pharmacy
2019 PATTERN.
ESR spectroscopy in liquid food and beverages.pptx
With increasing population, people need to rely on packaged food stuffs. Packaging of food materials requires the preservation of food. There are various methods for the treatment of food to preserve them and irradiation treatment of food is one of them. It is the most common and the most harmless method for the food preservation as it does not alter the necessary micronutrients of food materials. Although irradiated food doesn’t cause any harm to the human health but still the quality assessment of food is required to provide consumers with necessary information about the food. ESR spectroscopy is the most sophisticated way to investigate the quality of the food and the free radicals induced during the processing of the food. ESR spin trapping technique is useful for the detection of highly unstable radicals in the food. The antioxidant capability of liquid food and beverages in mainly performed by spin trapping technique.
Randomised Optimisation Algorithms in DAPHNE
Slides from talk:
Aleš Zamuda: Randomised Optimisation Algorithms in DAPHNE .
Austrian-Slovenian HPC Meeting 2024 – ASHPC24, Seeblickhotel Grundlsee in Austria, 10–13 June 2024
https://ashpc.eu/
The binding of cosmological structures by massless topological defects
Assuming spherical symmetry and weak field, it is shown that if one solves the Poisson equation or the Einstein field
equations sourced by a topological defect, i.e. a singularity of a very specific form, the result is a localized gravitational
field capable of driving flat rotation (i.e. Keplerian circular orbits at a constant speed for all radii) of test masses on a thin
spherical shell without any underlying mass. Moreover, a large-scale structure which exploits this solution by assembling
concentrically a number of such topological defects can establish a flat stellar or galactic rotation curve, and can also deflect
light in the same manner as an equipotential (isothermal) sphere. Thus, the need for dark matter or modified gravity theory is
mitigated, at least in part.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/Nucleic Acid-its structural and functional complexity.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Deep Software Variability and Frictionless Reproducibility
Deep Software Variability and Frictionless ReproducibilityUniversity of Rennes, INSA Rennes, Inria/IRISA, CNRS
The ability to recreate computational results with minimal effort and actionable metrics provides a solid foundation for scientific research and software development. When people can replicate an analysis at the touch of a button using open-source software, open data, and methods to assess and compare proposals, it significantly eases verification of results, engagement with a diverse range of contributors, and progress. However, we have yet to fully achieve this; there are still many sociotechnical frictions.
Inspired by David Donoho's vision, this talk aims to revisit the three crucial pillars of frictionless reproducibility (data sharing, code sharing, and competitive challenges) with the perspective of deep software variability.
Our observation is that multiple layers — hardware, operating systems, third-party libraries, software versions, input data, compile-time options, and parameters — are subject to variability that exacerbates frictions but is also essential for achieving robust, generalizable results and fostering innovation. I will first review the literature, providing evidence of how the complex variability interactions across these layers affect qualitative and quantitative software properties, thereby complicating the reproduction and replication of scientific studies in various fields.
I will then present some software engineering and AI techniques that can support the strategic exploration of variability spaces. These include the use of abstractions and models (e.g., feature models), sampling strategies (e.g., uniform, random), cost-effective measurements (e.g., incremental build of software configurations), and dimensionality reduction methods (e.g., transfer learning, feature selection, software debloating).
I will finally argue that deep variability is both the problem and solution of frictionless reproducibility, calling the software science community to develop new methods and tools to manage variability and foster reproducibility in software systems.
Exposé invité Journées Nationales du GDR GPL 2024
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...University of Maribor
Slides from talk:
Aleš Zamuda: Remote Sensing and Computational, Evolutionary, Supercomputing, and Intelligent Systems.
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Inter-Society Networking Panel GRSS/MTT-S/CIS Panel Session: Promoting Connection and Cooperation
https://www.etran.rs/2024/en/home-english/EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
represent the most massive star-forming environment that is dominated by the feedback from massive stars and gravitational interactions
among stars.
Aims. In this paper we present the Extended Westerlund 1 and 2 Open Clusters Survey (EWOCS) project, which aims to investigate
the influence of the starburst environment on the formation of stars and planets, and on the evolution of both low and high mass stars.
The primary targets of this project are Westerlund 1 and 2, the closest supermassive star clusters to the Sun.
Methods. The project is based primarily on recent observations conducted with the Chandra and JWST observatories. Specifically,
the Chandra survey of Westerlund 1 consists of 36 new ACIS-I observations, nearly co-pointed, for a total exposure time of 1 Msec.
Additionally, we included 8 archival Chandra/ACIS-S observations. This paper presents the resulting catalog of X-ray sources within
and around Westerlund 1. Sources were detected by combining various existing methods, and photon extraction and source validation
were carried out using the ACIS-Extract software.
Results. The EWOCS X-ray catalog comprises 5963 validated sources out of the 9420 initially provided to ACIS-Extract, reaching a
photon flux threshold of approximately 2 × 10−8 photons cm−2
s
−1
. The X-ray sources exhibit a highly concentrated spatial distribution,
with 1075 sources located within the central 1 arcmin. We have successfully detected X-ray emissions from 126 out of the 166 known
massive stars of the cluster, and we have collected over 71 000 photons from the magnetar CXO J164710.20-455217.
Equivariant neural networks and representation theory
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
Recently uploaded (20)
aziz sancar nobel prize winner: from mardin to nobel
aziz sancar nobel prize winner: from mardin to nobel
bordetella pertussis.................................ppt
bordetella pertussis.................................ppt
mô tả các thí nghiệm về đánh giá tác động dòng khí hóa sau đốt
mô tả các thí nghiệm về đánh giá tác động dòng khí hóa sau đốt
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...
ESR spectroscopy in liquid food and beverages.pptx
ESR spectroscopy in liquid food and beverages.pptx
The binding of cosmological structures by massless topological defects
The binding of cosmological structures by massless topological defects
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...
Nucleic Acid-its structural and functional complexity.
Nucleic Acid-its structural and functional complexity.
Deep Software Variability and Frictionless Reproducibility
Deep Software Variability and Frictionless Reproducibility
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...
Remote Sensing and Computational, Evolutionary, Supercomputing, and Intellige...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
EWOCS-I: The catalog of X-ray sources in Westerlund 1 from the Extended Weste...
Equivariant neural networks and representation theory
Equivariant neural networks and representation theory
chem_section_10.3_powerpoint.ppt
- 1. © 2014 Pearson Education, Inc. Chapter 10 Lecture Basic Chemistry Fourth Edition Electronegativity and Polarity Learning Goal Use electronegativity to determine the polarity of a bond or a molecule.
- 2. © 2014 Pearson Education, Inc. Electronegativity and Polarity We can learn more about the chemistry of compounds by understanding how electrons are shared in bonds. • Bonds formed by identical atoms share the bonding electrons equally. • Bonds formed between different atoms share the bonding electrons unequally.
- 3. © 2014 Pearson Education, Inc. Electronegativity Electronegativity • is the relative ability of atoms to attract shared electrons • is higher for nonmetals; fluorine has the highest with a value of 4.0 • is lower for metals; cesium and francium have the lowest value of 0.7
- 4. © 2014 Pearson Education, Inc. Electronegativity We can use the periodic table to predict the relative electronegativity value for each element. Electronegativity • increases from left to right going across a period on the periodic table • decreases going down a group on the periodic table
- 5. © 2014 Pearson Education, Inc. Electronegativity Figure 10.1 The electronegativity values of the representative elements in Group 1A (1) to Group 7A (17), which indicate the ability of atoms to attract shared electrons, increase going across a period from left to right and decrease going down a group.
- 6. © 2014 Pearson Education, Inc. Learning Check Using the periodic table, predict the order of increasing electronegativity for the elements O, K, and C.
- 7. © 2014 Pearson Education, Inc. Solution Using the periodic table, predict the order of increasing electronegativity for the elements O, K, and C. Answer: K, C, O • K, period 4, group 1A (1), has an electronegativity value of 0.8. • C, period 2, group 4A (14), has an electronegativity value of 2.5. • O, period 2, group 6A (16), has an electronegativity value of 3.5.
- 8. © 2014 Pearson Education, Inc. Types of Covalent Bonds Bonds can be described by the difference in the electronegativity of the bonding atoms. Two types of covalent bonds occur in molecules: • nonpolar covalent bonds; bonding electrons are shared equally • polar covalent bonds; bonding electrons are shared unequally
- 9. © 2014 Pearson Education, Inc. Nonpolar Covalent Bonds A nonpolar covalent bond between nonmetal atoms • consists of an equal (or almost equal) sharing of electrons • has a zero (or close to zero) electronegativity difference (0.0 to 0.4)
- 10. © 2014 Pearson Education, Inc. Polar Covalent Bonds A polar covalent bond between nonmetal atoms • consists of an unequal sharing of electrons • has an electronegativity difference of 0.5 to 1.7
- 11. © 2014 Pearson Education, Inc. Polar and Nonpolar Covalent Bonds Figure 10.2 In the nonpolar covalent bond of H2, electrons are shared equally. In the polar covalent bond of HCl, electrons are shared unequally.
- 12. © 2014 Pearson Education, Inc. Dipoles and Bond Polarity • Bonds become more polar as the difference in electronegativity increases. • A polar covalent bond that has a separation of charges is called a dipole. • The positive and negative ends are represented by the Greek letter delta, with a + or − charge. • Arrows can also be used to represent dipoles.
- 13. © 2014 Pearson Education, Inc. Variations in Bonding Variations in bonding are continuous. • Bonds with an electronegativity difference of 0.0 – 0.4 are considered nonpolar. • Bonds with an electronegativity difference of 0.5 – 1.7 are considered polar covalent. • Bonds with an electronegativity difference greater than 1.8 are considered ionic.
- 14. © 2014 Pearson Education, Inc. Electronegativity and Types of Bonds
- 15. © 2014 Pearson Education, Inc. Predicting Bond Type
- 16. © 2014 Pearson Education, Inc. Learning Check Complete the following table for each of the bonds indicated.
- 17. © 2014 Pearson Education, Inc. Solution Complete the following table for each of the bonds indicated.
- 18. © 2014 Pearson Education, Inc. Polarity of Molecules—Nonpolar In a nonpolar molecule, all the bonds are nonpolar, or the polar bonds (dipoles) cancel each other out. Molecules such as H2, Cl2 and CH4 are nonpolar because they contain only nonpolar bonds.
- 19. © 2014 Pearson Education, Inc. Polarity of Molecules—Nonpolar A nonpolar molecule also occurs when polar bonds (dipoles) cancel each other because of a symmetrical arrangement. Molecules such as CO2 and CCl4 contain polar bonds with dipoles that cancel each other out.
- 20. © 2014 Pearson Education, Inc. Polarity of Molecules—Polar A polar molecule occurs when the dipoles from individual bonds do not cancel each other out. For molecules with two or more electron groups, the shape (such as bent or trigonal pyrimidal) determines whether or not the dipoles cancel.
- 21. © 2014 Pearson Education, Inc. Polarity of Molecules—Polar Examples of polar molecules include HCl, H2O, and NH3. • HCl is linear and contains a polar bond. • H2O is bent and contains two polar bonds as well as two lone pairs on oxygen.
- 22. © 2014 Pearson Education, Inc. Polarity of Molecules—Polar • NH3 is trigonal pyrimidal, and contains three polar bonds and a lone pair on nitrogen.
- 23. © 2014 Pearson Education, Inc. Guide to Determination of Polarity of a Molecule
- 24. © 2014 Pearson Education, Inc. Learning Check Determine if the molecule OF2 is polar or nonpolar.
- 25. © 2014 Pearson Education, Inc. Solution Determine if the molecule OF2 is polar or nonpolar. Step 1 Determine if the bonds are polar or nonpolar covalent. Oxygen has an electronegativity of 3.5, and fluorine has an electronegativity of 4.0. O—F bonds are polar covalent.
- 26. © 2014 Pearson Education, Inc. Solution Determine if the molecule OF2 is polar or nonpolar. Step 2 If the bonds are polar covalent, draw the electron-dot formula and determine if the dipoles cancel. Dipoles in O—F bonds do not cancel; the molecule is polar.
- 27. © 2014 Pearson Education, Inc.