This document discusses intramolecular and intermolecular forces. It defines intramolecular forces as those within a molecule that hold atoms together, such as ionic, covalent, and metallic bonds. Intermolecular forces are weaker forces between molecules, including dipole-dipole, ion-dipole, hydrogen bonding, and London dispersion forces. The document explains each type of intramolecular and intermolecular force in more detail and notes that intramolecular bonds are stronger than intermolecular forces.
3. 3
Learning Objectives:
1. Differentiate intramolecular forces and
intermolecular forces of attraction.
2. Describe and differentiate the types of
intermolecular forces
3. Predict the intermolecular forces that
holds the molecules together.
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There are two kinds of forces that operate on a
molecule – intramolecular and intermolecular forces of
attraction.
Intramolecular
forces are the
forces within a
molecule or ionic
compound
8. Strength
Intramolecular bonds > intermolecular forces
Intramolecular bonds are stronger because it would take a
lot more energy to overcome covalent bonds and break
apart the molecule than to overcome intermolecular forces
in between the atoms (to make it become a liquid or gas).
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10. IONIC BOND
This bond is formed by the complete transfer of valence electron(s)
between atoms.
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It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses
electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become
a negatively charged anion.
11. COVALENT BOND
Covalent bond: This bond is formed between atoms that
have similar electronegativities—the affinity or desire for
electrons. Because both atoms have similar affinity for
electrons and neither tends to donate them, they share
electrons in order to achieve octet configuration and
become more stable.
• NONPOLAR COVALENT BOND
• POLAR COVALENT 11
14. METALLIC BOND
This type of covalent bonding specifically occurs between
atoms of metals, in which the valence electrons are free to
move through the lattice. This bond is formed via the
attraction of the mobile electrons—referred to as sea of
electrons—and the fixed positively charged metal ions.
Metallic bonds are present in samples of pure elemental
metals, such as gold or aluminum, or alloys, like brass or
bronze.
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15. LEARNING CHECK
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What is the intramolecular force that forms when atoms
share electrons?
a. Ionic
b. Covalent
16. LEARNING CHECK
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What is the intramolecular force that generates two
opposite charged ions?
a. Ionic
b. Covalent
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Intermolecular forces are the forces
between molecules or ions and molecules
are weaker than the
intramolecular forces of
attraction but are important
because they determine the
physical properties of
molecules like their boiling
point, melting point, density,
and enthalpies of fusion and
vaporization.
1.Dipole-dipole interaction
2.Ion Dipole Interaction
3.Hydrogen Bonding
4.London Dispersion Forces
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DIPOLE-DIPOLE FORCES
These are forces of attraction that occur between positive end of one
polar molecule and the negative end of another polar molecule.
Dipole-dipole interactions are the strongest intermolecular force of
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ION-DIPOLE FORCES
These are attractive forces that occur between an ion and a polar
molecule. These are mostly found in solutions.
A positive ion
(cation) attracts the
partially negative
end of a neutral
polar molecule.
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HYDROGEN BONDING
This is a special kind of dipole-dipole interaction that occurs specifically
between a hydrogen atom bonded to either an oxygen, nitrogen, or
fluorine atom.
Hydrogen just
wanna have
FON!
The partially positive end of
hydrogen is attracted to the
partially negative end of the
oxygen, nitrogen, or fluorine of
another molecule.
Hydrogen bonding is a relatively strong force of attraction between molecules, and considerable
energy is required to break hydrogen bonds. This explains the exceptionally high boiling points
and melting points of compounds like water, H2O and hydrogen fluoride, HF.
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LONDON DISPERSION FORCES
These are the weakest of the intermolecular forces and exist between all
types of molecules, whether ionic or covalent—polar or nonpolar. The more
electrons a molecule has, the stronger the London dispersion forces are.
For example, bromine, has more electrons than chlorine, so
bromine will have stronger London dispersion forces than
chlorine, resulting in a higher boiling point for bromine, 59 degree
Celsius compared to chlorine, –35 degree Celsius.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.