Chemistry chapter 5

change volume into volume when at

same temperature and pressure

volume of a gas varies directly with

the absolute temperature at constant pressure

Consider three 1-L flasks at STP. Flask A contains NH3 gas, flask B contains NO2 gas, and flask C contains N2 gas. Which contains the largest number of molecules?

All are the same.

Consider three 1-L flasks at STP. Flask A contains NH3 gas, flask B contains NO2 gas, and flask C contains N2 gas. In which flask do the molecules have the highest average velocity?

Flask A

Consider three 1-L flasks at STP. Flask A contains NH3 gas, flask B contains NO2 gas, and flask C contains N2 gas. In which flask are the molecules least polar and therefore most ideal in behavior?

Flask C

Which of the following is not a postulate of the kinetic molecular theory? a. Gas particles have most of their mass concentrated in the nucleus of the atom. b. The moving particles undergo perfectly elastic collisions with the walls of the container. c. The forces of attraction and repulsion between the particles are insignificant. d. The average kinetic energy of the particles is directly proportional to the absolute temperature. e. All of the above are postulates of the kinetic molecular theory.

a. Gas particles have most of their mass concentrated in the nucleus of the atom.

Calculate the ratio of the effusion rates of N2 and N2O. a. 0.637 b. 1.25 c. 1.57 d. 0.798 e. 1.61

b. 1.25 (Velocity A/velocity gas B = root MM gas B/MM gasA)

What would happen to the average kinetic energy of the molecules of a gas sample if the temperature of the sample increased from 20°C to 40°C? a. It would double. b. It would increase. c. It would decrease. d. It would become half its value. e. Two of these.

b. It would increase.

Which of the following is true about the kinetic molecular theory? a. The volume of a gas particle is considered to be small - about 0.10 mL. b. Pressure is due to the collisions of the gas particles with the walls of the container. c. Gas particles repel each other, but do not attract one another. d. Adding an ideal gas to a closed container will cause an increase in temperature. e. At least two of the above statements are correct.

b. Pressure is due to the collisions of the gas particles with the walls of the container.

One way to isolate metals from their ores is to react the metal oxide with carbon as shown in the following reaction: 2MO(s) + C(s) → 2M(s) + CO2(g) If 31.50 g of a metal oxide reacted with excess carbon and 1.48 L of CO2 formed at 100ºC and 1.50 atm, what is the identity of the metal? No answer provided a. Cu b. Cr c. Hg d. Cd e. Mg

c. Hg

Complete the following: Because real gas particles have attraction for one another: a. Real gases act most ideally at STP. b. We assume gas particles have negligible (zero) volume. c. One mole of an ideal gas at STP has a volume of 22.4 L. d. Real gases act more ideally at higher temperatures and lower pressures. e. At least two of the above statements (A-D) correctly complete the statement.

d. Real gases act more ideally at higher temperatures and lower pressures.

pressure and temperature have a(n) ____________ relationship

direct

at constant volume, pressure and absolute temperature are __________ related

directly

Given a cylinder of fixed volume filled with 1 mol of argon gas, which of the following is correct? (Assume all gases obey the ideal gas law.) a. If the temperature of the cylinder is changed from 25°C to 50°C, the pressure inside the cylinder will double. b. If a second mole of argon is added to the cylinder, the ratio T/P would remain constant. c. A cylinder of identical volume filled with the same pressure of helium must contain more atoms of gas because He has a smaller atomic radius than argon. d. Two of the above. e. None of the above.

e. None of the above.

Hydrogen and chlorine gases react to form HCl. You and a friend are on opposite sides of a long hallway, you with H2 and your friend with Cl2. You both want to form HCl in the middle of the room. Which of the following is true? a. You need to know the temperature to answer this question. b. You need to know the length of the room to answer this question. c. You should release the H2 first. d. You both should release the gases at the same time. e. Your friend should release the Cl2 first.

e. Your friend should release the Cl2 first.

ideal gases do not exert ___________ on each other

intermolecular forces

pressure and volume have a(n) __________ relationship at constant temperature

inverse

gases approach ideal at

low pressures, high temperatures

at constant temperature and pressure the volume of gas is directly related to

moles

when problem says collected over water:

subtract pressures

mass is not affected by

temperature or pressure

A hot-air balloon rises. what is best explanation?

the air density inside the balloon is less than that of the surrounding air.