Q: Calculate the root mean square velocity ($$u_{rms}) of $$helium atoms at $$300\ \mathrm{K}$$. ($$M = 4.00\ \mathrm{g/mol}$$, $$R = 8.314\ \mathrm{J\ $$mol^{-1}$$\ K$$^{-1}$$}$$; $$u_{rms} = \sqrt{\frac{3RT}{M}}$$, with $$M in kg/$$mol)

$$1.37 \times 10^3$\ \mathrm{m/s}$$

Q: What is the wavelength of light with a frequency of $$6.0 \times 10$$^{14}$$\ \mathrm{Hz}$$? (Speed of light $$c = 3.00 \times 10^8$\ \mathrm{m/s}$$; $$c = \lambda \nu)$$

$$5.0 \times 10$$^{-7}$$\ \mathrm{m}$$

Q: According to the de Broglie relation, what is the wavelength of an electron ($$m = 9.11 \times 10$$^{-31}$$\ \mathrm{kg}) $$moving at $$2.0 \times 10^6$\ \mathrm{m/s}$$? ($$\lambda = \frac{h}{mv}$$, $$h = 6.626 \times 10$$^{-34}$$\ \mathrm{J\ s})$$

$$3.6 \times 10$$^{-10}$$\ \mathrm{m}$$

Q: A hydrogen atom electron transitions from $$n=4 to$$ $$n=2. $$What is the energy of the photon emitted? ($$E = -2.18 \times 10$$^{-18}$$\ \mathrm{J} \left( \frac{1}{n_f^2$} - \frac{1}{n_i^2$} \right))$$

$$4.09 \times 10$$^{-19}$$\ \mathrm{J}$$

Question 1

A scuba diver descends to a depth where the pressure is 3.0 atm. If the diver inhales 2.0 L of air at the surface (1.0 atm, 25°C), what will be the volume of this air in the diver's lungs at depth, assuming temperature remains constant? (Use Boyle’s Law: $$P_1V_1 = P_2V_2)$$

Accepted Answer

$$0.67\ \mathrm{L}$$

Question 2

Which of the following best describes the difference between an ideal gas and a real gas?

Accepted Answer

Ideal gases have no intermolecular forces and occupy no volume, while real gases have intermolecular forces and occupy finite volume.

Question 3

A sample of oxygen gas ($$O_2) $$has a density of $$1.43\ \mathrm{g/L} at$$ $$0^{\circ}$$\mathrm{C}$$ and 1.00$$\ \mathrm{atm}$$. What is the molar mass of O_2$ based on the ideal gas law? (Use R = 0.0821$$\ \mathrm{L\ atm\ $$mol^{-1}$$\ $$K^{-1}$$}$$)

Accepted Answer

$$32.0\ \mathrm{g/mol}$$

Question 4

A mixture contains $$2.0\ \mathrm{mol} of$$ $$N_2$$, $$1.0\ \mathrm{mol} of$$ $$O_2$$, and $$1.0\ \mathrm{mol} of$$ $$CO_2 in a$$ $$10.0\ \mathrm{L}$$ container at $$300\ \mathrm{K}. $$What is the partial pressure of $$O_2$$? (Use $$R = 0.0821\ \mathrm{L\ atm\ $$mol^{-1}$$\ K$$^{-1}$$})$$

Accepted Answer

$$0.82\ \mathrm{atm}$$

Question 5

Which of the following statements about the kinetic molecular theory is FALSE?

Accepted Answer

Gas particles lose energy during elastic collisions.

Question 6

Calculate the root mean square velocity ($$u_{rms}) of $$helium atoms at $$300\ \mathrm{K}$$. ($$M = 4.00\ \mathrm{g/mol}$$, $$R = 8.314\ \mathrm{J\ $$mol^{-1}$$\ K$$^{-1}$$}$$; $$u_{rms} = \sqrt{\frac{3RT}{M}}$$, with $$M in kg/$$mol)

Accepted Answer

$$1.37 	imes 10^3$\ \mathrm{m/s}$$

Question 7

A reaction in a bomb calorimeter releases $$5000\ \mathrm{J} of $$heat and the temperature of the calorimeter increases by $$2.5^{\circ}$$\mathrm{C}$$. What is the heat capacity of the calorimeter?

Accepted Answer

$$2000\ \mathrm{J$$/^{\circ}$$C}$$

Question 8

Which of the following processes is exothermic?

Accepted Answer

Combustion of methane in air

Question 9

A $$50.0\ \mathrm{g}$$ sample of water absorbs $$1045\ \mathrm{J} of $$heat. What is the temperature change? (Specific heat of water $$= 4.18\ \mathrm{J/g\ ^{\circ}C})$$

Accepted Answer

$$5.00^{\circ}$$\mathrm{C}$$

Question 10

Which of the following best describes the first law of thermodynamics?

Accepted Answer

Energy cannot be created or destroyed, only transferred or transformed.

Question 11

A $$2.0\ \mathrm{mol}$$ sample of an ideal gas expands from $$5.0\ \mathrm{L} to$$ $$10.0\ \mathrm{L} at a $$constant pressure of $$2.0\ \mathrm{atm}. $$How much work is done by the gas? ($$w = -P\Delta V$$; $$1\ \mathrm{L\ atm} = 101.3\ \mathrm{J})$$

Accepted Answer

$$-1013\ \mathrm{J}$$

Question 12

Which quantum number determines the shape of an atomic orbital?

Accepted Answer

Angular momentum quantum number ($$l)$$

Question 13

What is the wavelength of light with a frequency of $$6.0 	imes 10$$^{14}$$\ \mathrm{Hz}$$? (Speed of light $$c = 3.00 	imes 10^8$\ \mathrm{m/s}$$; $$c = \lambda 
u)$$

Accepted Answer

$$5.0 	imes 10$$^{-7}$$\ \mathrm{m}$$

Question 14

Which experiment provided evidence for the particle nature of light?

Accepted Answer

Photoelectric effect

Question 15

According to the de Broglie relation, what is the wavelength of an electron ($$m = 9.11 	imes 10$$^{-31}$$\ \mathrm{kg}) $$moving at $$2.0 	imes 10^6$\ \mathrm{m/s}$$? ($$\lambda = \frac{h}{mv}$$, $$h = 6.626 	imes 10$$^{-34}$$\ \mathrm{J\ s})$$

Accepted Answer

$$3.6 	imes 10$$^{-10}$$\ \mathrm{m}$$

Question 16

Which of the following statements is a consequence of Heisenberg’s uncertainty principle?

Accepted Answer

It is impossible to know both the exact position and exact momentum of an electron simultaneously.

Question 17

A hydrogen atom electron transitions from $$n=4 to$$ $$n=2. $$What is the energy of the photon emitted? ($$E = -2.18 	imes 10$$^{-18}$$\ \mathrm{J} \left( \frac{1}{n_f^2$} - \frac{1}{n_i^2$} ight))$$

Accepted Answer

$$4.09 	imes 10$$^{-19}$$\ \mathrm{J}$$

Question 18

Which of the following best describes constructive interference?

Accepted Answer

Two waves overlap in phase, resulting in increased amplitude.

Question 19

Which of the following is NOT a state function?

Accepted Answer

Heat ($$q)$$

General Chemistry Study Notes: Gases, Thermochemistry, and Quantum Mechanics

Study Guide - Practice Questions

Study Guide - Flashcards