Lewis Structures
IMFs
Vocabulary
Conversions/Polar vs Nonpolar
Miscellaneous
100
Draw the Lewis structure for BeF2. What is the molecular geometry?
Linear
100
Rank the following from strongest to weakest.
London Dispersion Forces, ion/ion, dipole/dipole, ion/dipole, dipole/induced dipole
ion/ion
ion/dipole
dipole/dipole
dipole/induced dipole
London Dispersion Forces
100
Define viscosity and give an everyday example of one fluid that is more viscous than another.
Viscosity: resistance of a liquid to flow
Ex. Syrup is more viscous than water.
100
Convert 18 grams of water to moles.
1
100
Write the chemical formula.
C20H30O
200
Write the Lewis structure for CCl4. What is the molecular geometry?
tetrahedral
200
What is the difference between an intramolecular force and an intermolecular force? Which one is an "IMF"?
intramolecular: between different molecules
intermolecular (IMFs): within the same molecule
Ex. INTERstate, INTERnational, etc.
200
Name and define the 6 phase transitions that we have gone over.
sublimation: solid to gas
deposition:gas to solid
vaporization: liquid to gas
condensation: gas to liquid
melting/fusion: solid to liquid
freezing: liquid to solid
200
How many grams are in 0.7 moles of H2O2?
23.8g
200
Which phase transitions have a negative ∆H? Which have a positive ∆H? What does this tell us about the processes?
Endothermic (positive ∆H), absorb heat:
vaporization, melting/fusion, sublimation
Exothermic (negative ∆H), release heat:
condensation, freezing, deposition
300
Draw the Lewis structure for BH2–. What is the molecular geometry?
bent
300
Define Hydrogen Bond.
Hydrogen - (N, O, F)
300
Define the critical point on a phase diagram.
The point at which at a greater temperature or pressure, fluid has both properties of a liquid and gas. Liquid cannot exist above the critical temperature regardless of the P
- at Critical Point, gas and liquid states form supercritical fluid
300
Is carbon tetrachloride polar or non polar? What is its molecular geometry?
non polar, tetrahedral
300
Name 3 factors that affect viscosity.
IMFs, molecular structure, temperature
400
Write the Lewis structure for NI3. What is the molecular geometry?
trigonal pyramidal
400
Rank the following from greatest to smallest boiling point. What is the dominant IMF in each?
CH4, NaCl, C5H12
NaCl, C5H12, CH4
ion-ion; dispersion; dispersion
400
Define normal boiling point? How is boiling point affected by altitude?
Normal BP is at 1atm of pressure. At higher altitudes (less pressure) the boiling point decreases.
400
Is SeF6 polar or non polar? what is its molecular geometry?
non polar, octahedral
400
How does temperature affect IMFs?
Greater temperature = weaker IMFs
500
Write the Lewis structure for SI6 .What is the molecular geometry?
octahedral
500
Rank the following from weakest to strongest:
H-bond, London dispersion, dipole-dipole
H-bond>dipole-dipole>London
500
Define vapor pressure. How does it relate to IMFs?
pressure exerted by the vapor of a substance in a closed system at equilibrium. Weaker IMFs correspond to greater vapor pressure (it evaporates more easily).
500
Is ammonia polar or non polar? what is its molecular geometry?
polar; trigonal pyramidal
500
Write the Clausius-Clapeyron Equation.
LnP2/P1= Hvap/R(1/T1-1/T2)