Question 1

Which of the following best describes the vaporization curve on a phase diagram?

Accepted Answer

It separates the liquid and gas phases.

Question 2

A 94.4 g sample of benzene (molar mass = 78.11 g/mol) is cooled from its melting point (279.0 K) to 205.0 K and solidified. Given $$\Delta H_{fus} = 9.8\ \mathrm{kJ/mol}$$ and $$C_{sol} = 1.51\ \mathrm{J/g\cdot K}$$, how much energy must be removed?

Accepted Answer

$$29.4\ \mathrm{kJ}$$

Question 3

What is the correct name for the compound $$\mathrm{Sn(SO_4$)_2}$$?

Accepted Answer

tin(IV) sulfate

Question 4

What is the percent yield of Fe if 28.65 g of Fe is produced from 50.00 g of $$\mathrm{Fe_2O_3}$$ and excess Al according to $$\mathrm{Fe_2O_3} + 2\mathrm{Al} \rightarrow \mathrm{Al_2O_3} + 2\mathrm{Fe}$$?

Accepted Answer

57.30%

Question 5

Which of the following is the empirical formula for a compound that is 70.79% C, 8.91% H, 4.59% N, and 15.72% O by mass?

Accepted Answer

$$\mathrm{C$$_{17}$$H_{27}NO_3$}$$

Question 6

Which of the following statements about thermochemistry is FALSE?

Accepted Answer

An endothermic reaction gives off heat to the surroundings.

Question 7

A reaction in a coffee cup calorimeter causes the temperature to fall below room temperature. Which statement is TRUE?

Accepted Answer

None of the above statements is true.

Question 8

Which of the following molecules has $$sp^2$$ hybridization on the central atom? (HCN, SO$$_2$$, OCl$$_2$$, XeCl$$_2)$$

Accepted Answer

2

Question 9

Which of the following best defines electronegativity?

Accepted Answer

The ability of an atom to attract electrons to itself in a chemical bond.

Question 10

Which of the following signs on $$q$$ and $$w$$ represent a system that is doing work on the surroundings and losing heat to the surroundings?

Accepted Answer

$$q = -, w = -$$

Question 11

Which of the following statements is TRUE regarding intermolecular forces?

Accepted Answer

Hydrogen bonds are stronger than dipole-dipole forces.

Question 12

What is the theoretical yield of HCl if 50.0 g of $$\mathrm{$$BCl_3$$}$$ and 31.2 g of $$\mathrm{H_2O}$$ are reacted according to $$\mathrm{$$BCl_3$$(g) + 3 H_2O(l) \rightarrow H_3BO_3(s) + 3 HCl(g)}$$? (Molar mass $$\mathrm{$$BCl_3$$} = 117.16\ \mathrm{g/mol})$$

Accepted Answer

15.5 g HCl

Question 13

Which of the following best describes sublimation?

Accepted Answer

The phase transition from solid to gas.

Question 14

Place the following in order of decreasing magnitude of lattice energy: $$\mathrm{K_2O}$$, $$\mathrm{Rb_2S}$$, $$\mathrm{Li_2O}.$$

Accepted Answer

$$\mathrm{Li_2O \u003e K_2O \u003e Rb_2S}$$

Question 15

Which of the following best describes the forces between ionic compounds and polar compounds?

Accepted Answer

Ion-dipole forces.

Question 16

Calculate the mass percent composition of lithium in $$\mathrm{Li_3PO_4}.$$

Accepted Answer

26.75%

Question 17

Which of the following best describes energy associated with the temperature of an object?

Accepted Answer

Thermal energy.

Question 18

Rank the following molecules in decreasing bond strength: $$\mathrm{Cl_2$}$$, $$\mathrm{Br_2$}$$, $$\mathrm{F_2$}$$, $$\mathrm{I_2$}.$$

Accepted Answer

$$\mathrm{Cl_2$ \u003e Br_2$ \u003e F_2$ \u003e I_2$}$$

Question 19

What is the molarity of a solution formed by dissolving 3.00 moles of NaCl in enough water to yield 4.00 L of solution?

Accepted Answer

0.750 M

Question 20

Place the following substances in order of decreasing vapor pressure at a given temperature: NaCl, CH$$_3OH$$, OF$$_2.$$

Accepted Answer

OF$$_2$$ \u003e CH$$_3OH$$ \u003e NaCl

General Chemistry 111B Review: Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard