$q = m \times C_s \times \Delta T$

$\Delta H_{rxn} = \sum n_p \Delta H_f^\circ (\text{products}) - \sum n_r \Delta H_f^\circ (\text{reactants})$

Question 1

Which of the following best describes a precipitation reaction?

Accepted Answer

A reaction in which an insoluble solid forms from the mixing of two aqueous solutions.

Question 2

Given the reaction: $\mathrm{NaOH} + \mathrm{HCl} \rightarrow \mathrm{NaCl} + \mathrm{H_2O}$, what type of reaction is this?

Accepted Answer

Neutralization reaction

Question 3

Which of the following is the correct formula for calculating the heat ($q$) absorbed by a substance?

Accepted Answer

$q = m 	imes C_s 	imes \Delta T$

Question 4

A student mixes 50.0 mL of 1.0 M $\mathrm{AgNO_3}$ with 50.0 mL of 1.0 M $\mathrm{NaCl}$. What is the precipitate formed?

Accepted Answer

$\mathrm{AgCl}$

Question 5

Which of the following metals is most reactive according to the reactivity series provided?

Accepted Answer

Potassium

Question 6

What is the correct formula for the kinetic energy of a gas molecule?

Accepted Answer

$KE = \frac{1}{2}mv^2$

Question 7

Which equation would you use to calculate the pressure of a gas using the ideal gas law?

Accepted Answer

$P = \frac{nRT}{V}$

Question 8

A solution contains 0.5 mol of $\mathrm{Na_2SO_4}$ in 1.0 L of water. What is the concentration of $\mathrm{SO_4^{2-}}$ ions?

Accepted Answer

0.5 M

Question 9

Which of the following is a state function?

Accepted Answer

Enthalpy

Question 10

If 100.0 g of water is heated from 25°C to 75°C, how much heat is absorbed? ($C_s$ for water = $4.184 \mathrm{J/g}^\circ\mathrm{C}$)

Accepted Answer

$20,920 \mathrm{J}$

Question 11

Which of the following is the correct expression for the standard enthalpy of reaction?

Accepted Answer

$\Delta H_{rxn} = \sum n_p \Delta H_f^\circ (	ext{products}) - \sum n_r \Delta H_f^\circ (	ext{reactants})$

Question 12

A gas occupies 2.0 L at 1.0 atm. If the pressure is increased to 2.0 atm at constant temperature, what is the new volume?

Accepted Answer

1.0 L

Question 13

Which of the following is true about strong acids?

Accepted Answer

They completely ionize in water.

Question 14

Which equation is used to calculate the partial pressure of a gas in a mixture?

Accepted Answer

$P_i = X_i P_{total}$

Question 15

A sample of gas at STP has a volume of 22.4 L. How many moles of gas are present?

Accepted Answer

1.0 mol

Question 16

Which of the following is NOT a property of an ideal gas?

Accepted Answer

Gas particles have significant volume.

Question 17

Which of the following is the correct formula for molarity?

Accepted Answer

$M = \frac{n}{V}$

Question 18

A solution is prepared by dissolving 0.25 mol of $\mathrm{KBr}$ in enough water to make 500 mL of solution. What is the molarity?

Accepted Answer

0.50 M

Question 19

Which of the following statements about Hess's Law is correct?

Accepted Answer

The enthalpy change of a reaction is independent of the pathway taken.

Question 20

Which of the following is the correct formula for calculating the average speed of a gas molecule?

Accepted Answer

$u_{avg} = \sqrt{\frac{3RT}{M}}$

General Chemistry Exam 2 Study Guide: Thermochemistry, Gas Laws, and Reactivity

Study Guide - Practice Questions