Chapter 11 - Solutions

Question 0

Intermolecular forces in order by strength

Answer 0

1. Hydrogen Bonding (O-H, N-H, F-H)
2. Dipole-Dipole (Polar compounds)
3. London Dispersion (Nonpolar)

Question 1

Intramolecular forces in order by strength

Answer 1

1. Covalent (Strongest - Nonmetals Sharing electrons)
2. Ionic Bonding (Nonmetal w/ Metal)
3. Metallic Bonding (Positive Metal ions surrounded by a sea of free-flowing electrons)
4. Ion-Dipole attraction (Ion w/ molecule)

Question 2

Heat/Enthalpy of Solution

Answer 2

The enthalpy change associated with the formation if the solution.

Question 3

∆Hsoln=∆H₁+ ∆H₂ + ∆H₃

Which are exothermic and which are endothermic?

Answer 3

∆H₁ - endothermic (taking in energy to break bonds)
∆H₂ - endothermic (taking in energy to break bonds)
∆H₃ - exothermic (releasing of energy from formation of bonds)

Question 4

Difference between ideal solution an nonideal solution

Answer 4

Ideal: Heat in = Heat out
(No change in enthalpy)

Nonideal: Heat in ≠ Heat out

Question 5

What dissolves…

1. An ionic solute
2. A polar solute
3. A non-polar solute

Answer 5

1. A polar solvent
2. A polar solvent
3. A non-polar solvent

Question 6

Henry’s Law states that…

Answer 6

The solubility of the gas is directly proportional to the gas above the solution.
S₁/P₁=constant=S₂/P₂

Question 7

Raoult’s Law states that the vapor pressure of a volatile liquid in a solution is directly proportional to…

Answer 7

1. The vapor pressure of the liquid
2. The concentration if the liquid in the solution (mole fraction)

Pₐ=xₐP˚

Question 8

Pₐ=xₐP˚

Define each term

Answer 8

Pₐ = vapor pressure above the solution
xₐ = mole fraction in liquid state
P˚ = vapor pressure of the pure liquid

Question 9

Define vapor pressure.

Answer 9

Pressure of a gas above a liquid at equilibrium.

Question 10

Raoult’s Law for 2 volatile liquids

Answer 10

Pt=Pₐ + Pb

Xₐ=Pₐ/Pt

Question 11

The solute is always the ____ part of the solution

Answer 11

Smaller

Question 12

The solvent is always the ____ part of the solution

Answer 12

Larger

Question 13

A solution with water as its solvent is…

Answer 13

Aqueous

Question 14

Formula for Molarity

Answer 14

M=n/V

Molarity=moles of solute/total volume

Question 15

Formula for Mole Fraction

Answer 15

Xₐ=nₐ/nt

Xₐ=nₐ/(nₐ+nb)

Question 16

Formula for Mass Percent

Answer 16

%=mₐ/(mₐ+mb) x 100%

Question 17

Formula for Molality

Answer 17

m=nₐ/kg solvent

Question 18

What makes a molecular compound nonpolar?

Answer 18

• Electronegativity of less than .4
• Symmetry
• The same element together (Cl₂)

Question 19

What is Hydrogen bonding?

Answer 19

The strongest intermolecular force between polar molecules. Only happens in O-H, N-H, and F-H compounds.

Question 20

What is dipole-dipole bonding?

Answer 20

The middle strength force for intermolecular bonds which happens between polar molecules.

Question 21

What is London Dispersion?

Answer 21

Intermolecular bonding for nonpolar molecules.

Stronger in long hydrocarbons, straight hydrocarbons, and larger atoms.

Question 22

What is the attraction force in ionic bonds?

Answer 22

Electrostatic forces

Question 23

Name the law that governs ionic bonding

Answer 23

Coulomb’s Law

Question 24

What is Coulomb’s law? According to this law, what is ionic bonding strongest for?

Answer 24

F=kqq/r²

q: size of charges
r: distance between centers

Therefore: Ionic bonding is strongest for small ions and those with high charges