ch. 11 & 3 IMF & stoichiometry ap chem
For problems involving calculations, show the relevant equation (or formula and conversion factor(s)), show your work in an organized manner, put the proper units in your calculations / answer, and have the proper number of significant figures in your answer. [70 points]
1. Which compound,
CH4 , CH3 CH3 , or CH3 CH2 CH3
has the highest boiling point ? highest vapor pressure ? Justify your answer; include the term, polarizability. [10 points]
2. Identify the type of IMF in each molecule
CH3 Cl; CH4 ; CCl4
include the basis of your choice. [10 points]
3. Balance the following chemical reactions using the lowest ratio of coefficients; include a “1” as appropriate; need not show work. [15 points]
a. an aqueous solution of calcium chloride reacts with another aqueous solution of sodium phosphate to form solid calcium phosphate and an aqueous solution of sodium chloride.
b. ___ Al + ___ H2 SO4 --> Al2 (SO4 )3 + ___ H2
c. ___ Be2 C + ___ H2 O --> ___ CH4 + ___ Be(OH)2
4. In regards the chemical reaction [15 points]
C2 H6 + O2 --> CO2 + H2 O
a. write the balanced chemical equation using the lowest ratio of coefficients.
b. How many grams of water would be produced by mixing 10.0 gram of C2 H6 and 30.0 grams of O2 ? [hint: identify the limiting reactant]
5. Rationalize the relative boiling point of the following chemicals; include “what does dipole moment measure ?” in your answer. [10 points]
chemical formula
molar mass (g / mol)
dipole moment (D)
boiling point (K)
CH3 CH2 CH3
44
0.1
231
CH3 OCH3
46
1.3
248
CH3 Cl
50
1.9
249
CH3 CHO (aldehyde)
44
2.7
294
CH3 CN
41
3.9
355
6. old topic: What are five of the possible 4 quantum numbers (n, l, ml , ms ) of a __ atomic orbital ? [10 points]
a. 3p
b. 4d