Lesson 1 Intro to Chemical Bonding
Upcoming SlideShare
Loading in...5
×
 

Lesson 1 Intro to Chemical Bonding

on

  • 3,333 views

Covalent Bonding Unit

Covalent Bonding Unit
Lesson 1 Intro to Bonding

Statistics

Views

Total Views
3,333
Views on SlideShare
3,327
Embed Views
6

Actions

Likes
0
Downloads
57
Comments
0

1 Embed 6

https://mj89sp3sau2k7lj1eg3k40hkeppguj6j-a-sites-opensocial.googleusercontent.com 6

Accessibility

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

Lesson 1 Intro to Chemical Bonding Lesson 1 Intro to Chemical Bonding Presentation Transcript

  • Lesson 1: Introduction to Chemical Bonding Covalent Bonding Unit
  • TargetsI can define chemical bond.I can describe covalent bonding.I can classify bonding type according to electronegativity differences.
  • DefinitionsChemical Bond – mutual electrical attraction between the nuclei and valence electrons of different atoms that bind the atoms togetherValence electrons – outermost electrons that are available to be lost, gained, or shared to form a chemical bond View slide
  • Chemical Bond A force that holds groups of 2 or more atoms together and makes them function as a unit Atom – smallest unit of an element Molecule – Group of covalently bonded atoms Atoms Molecule View slide
  • Types of Chemical BondsIonic Bonding – (covered in next chapter) a type of bond in which a metal and a nonmetal transfer electronsCovalent Bonding – type of bond in which 2 or more nonmetal atoms share electrons
  • IONIC – Metal + nonmetalPeriodic Table COVALENT – 2 nonmetals
  • Types of Covalent BondsNonpolar covalent bond – electrons are shared equally
  • Types of Chemical BondsPolar covalent – electrons are not shared equally because one atom attracts the shared electrons more than the other atom
  • Bond TypesVideo
  • ElectronegativityElectronegativity - measure of an atom’s ability to attract electrons.Electronegativities tend to increase across a period and decrease down a group
  • Classifying Chemical BondsThe polarity of a bond depends on the difference between the electronegativity values of the atoms forming the bonds.Nonpolar covalent – 0 to 0.3Polar covalent – 0.4 to 1.7Ionic – greater than 1.8
  • Electronegativity ValuesIncreases from left to right across a periodDecreases down a group of representative elements
  • PracticeUse electronegativity values to classify the following bonds: a. Sulfur and Hydrogen b. Lithium and Fluorine c. Potassium and Chlorine d. Iodine and Bromine e. Carbon and Hydrogen
  • PracticeUse electronegativity values to classify the following bonds: a. Sulfur and Hydrogen 2.5 – 2.1 = 0.4; polar covalent b. Lithium and Fluorine 4.0 – 1.0 = 3.0; Ionic c. Potassium and Chlorine 3.0 – 0.8 = 2.2; Ionic d. Iodine and Bromine 2.8 – 2.5 = 0.3; Nonpolar covalent e. Carbon and Hydrogen 2.5 – 2.1 = 0.4 ; polar covalent
  • Covalent BondingCovalent Bonding and Molecular Compounds
  • TargetsI can explain why most atoms form chemical bonds.I can explain the relationships among potential energy, distance between approaching atoms, bond length and bond energy.I can state the octet rule.I can determine the number of valence electrons for a given atom.
  • Formation of a Covalent BondNature favors chemical bonding because most atoms have lower potential energy when they are bonded to other atoms.
  • Formation of a Covalent BondEach atom has a positive nucleus in the center and negative electrons surrounding the nucleus in a spherical pattern.The positively charged nuclei are attracted to the negatively charged electrons.
  • Formation of a Covalent BondAs the atoms approach each other, the charged particles interact: nucleus on one atom attracts electrons on the other atom.
  • Formation of a Covalent BondAs the atoms approach one another, the potential energy decreases.A bond forms when the potential energy is at a minimum.
  • Formation of a Covalent BondIf the atoms continue to approach one another once the bond forms, the nuclei will begin to repel one another and the potential energy will start to increase.
  • Characteristics of the Covalent Bond Bond length – distance between two bonded atoms at their minimum potential energy or the average distance between two bonded atoms Bond energy – energy required to break a chemical bond and form neutral isolated atoms - kilojoules per mole (kJ/mol) Bond lengths and bond energies vary with the types of atoms that have combined
  • The Octet RuleThe octet rule states that atoms tend to lose, gain or share electrons until they are surrounded by 8 electrons in their valence shell.The number of valence electrons is equal to the group number. (Groups 13-18; Group # -10)LABEL YOUR PERIODIC TABLE 1A 8A 2A 3A 4A 5A 6A 7A
  • PracticeWhat is the relationship between bond energy and bond length?
  • PracticeWhat is the relationship between bond energy and bond length? The bond length decreases as the strength of the bond increases.
  • PracticeArrange the following in order of increasing bond strength: C–Cl, C–I, H–F, and I–ISKIP
  • PracticeArrange the following in order of increasing bond strength: C–Cl, C–I, H–F, and I–I I-I, C-I, C-Cl, H-F
  • Practice ProblemsWhich pair of bonded atoms has the strongest bond?
  • Practice ProblemsWhich pair of bonded atoms has the strongest bond? H – F
  • Practice ProblemsWhich pair of bonded atoms has the weakest bond?
  • Practice ProblemsWhich pair of bonded atoms has the weakest bond? I – I
  • Practice ProblemsArrange the following bond lengths in order of increasing bond strength: 72 pm, 149 pm, 53 pm, and 398 pm SKIP
  • Practice ProblemsArrange the following bond lengths in order of increasing bond strength: 72 pm, 149 pm, 53 pm, and 398 pm 398 pm, 149 pm, 72 pm, 53 pm
  • Practice ProblemsDetermine the number of valence electrons in each of the following atoms. Lithium Sulfur Carbon Neon
  • Practice ProblemsDetermine the number of valence electrons in each of the following atoms. Lithium - 1 Sulfur - 6 Carbon -4 Neon - 8