Characteristics of
Solid:
Liquid:
Gas:
- Solid: Definite Volume & Shape
- Liquid: Definite Volume
- Gas: No Definite Shape or Volume
Liquid Intermolecular forces can and can't do what?
Can hold molecules together, but cant prevent them from sliding past each other
What are the Intermolecular Forces for Gas Molecules?
Zero
What is Deposition?
Gas to Solid
What is Sublimation?
Solid directly into Gas
Cations
Metals that tend to give up electrons
Anions
Non metals that tend to acquire electrons
What is an Ionic Bond?
Attraction between oppositely charged ions
Stronger than Covalent Bonds
What are Covalent Bonds?
Sharing of Electrons by overlapping electron clouds of two atoms
Weaker than Ionic Bonds
Valence Electrons
Electrons on the Outer Most Shell
Number of Valence electrons = Group Number
They all want eight (octet rule)
VSEPR Theory
Valence Shell Electron Pair Repulsion
The groups connected to central atoms want to get away from eachother
What is Pauling's concept of Electronegitivity?
More Electronegative atoms will tend to pull electrons towards themselves
Flourine is the most Electronegative
What is a Non-Polar Bond?
When two bonded atoms have the same electronegativity
What is a Polar Bond?
When two bonded atoms have different electronegativity.
The electrons are closer to the more electronegative atom
Creates Partial Charge
What are the main types of Intermolecular Forces?
Dipolar
Hydrogen Bonding
London Forces
Dipole-Dipole Attraction
Only happens between Polar Molecules or those of Opposite Partial Charges
Hydrogen Bonding
- Type of Dipolar Interation
- Only when directly bonded to F, O, N
- Stronger than Dipole-Dipole
- So when Hydrogen is bonded to F/O/N, that same Hydrogen highly attracts other things w/ partial negative charge
How is Hydrogen Bonding Important to the body?
- Keeps water in liquid state
- Holds DNA together
- Maintain Enzymes
Ion Dipole Attraction
- Attraction b/t Ionic & Polar Molecule
- Allows ionic solids to dissolve in water
- Strength depends on dipole moment
What are London Forces?
- Weakest, but Most Important and found Everywhere
- Occurs with uneven distribution of e- --> instant dipole
- Bigger molecules have bigger London Forces d/t more e-
- AKA Vander Waal Forces
What changes with more Intermolecular Forces?
↑Boiling & ↑Melting
↑Heat of Fusion & Vaporization
↑Viscosity
↓Vapor Pressure
Solubility
How does Intermolecular Forces relate to Surface Tension?
Greater Intermolecular Forces = Greater Surface Tension
According to LaPlace's Law, what is the relationship between surface tension and radius?
In a blood vessel, the surface tension is directly proportional to the radius of the vessel.
Tension = Pressure x Radius (Cylindrical)
LaPlace states in a blood vessel, the smaller the radius. the ________ pressure it can withstand
Smaller the radius of blood vessel, the more pressure it can withstand
How does surface tension act in a spherical shape?
Tension = Pressure x (Radius/2)
What are Surfactants?
Surface Active Agent, like soap, that reduces surface tension
What is Saponification?
Chemical Process of making soap from fats/oils
Soap is the salt of Fatty Acid
What is the Form of Soaps and Surfactants?
Polar head with Non-Polar (Hydrophobic) tail.
What are Micelles?
When the Non-Polar, Hydrophobic tails come together and form a sphere. This traps other greasy, water-insoluble things in the center.
Increase Intermolecular forces _______ viscosity
Increasing IM forces increases Viscosity
