CHEMISTRY

Chapter 13 Quiz, 2/14/08

(5 pts.)

  1. Indicate whether each statement is true or false.

F, not always The solid phase is always denser than the liquid phase.

F, bp is where Pvapor=Pexternal The boiling point is the temperature at which a substance evaporates.

_T___ Diamond is harder than graphite because of its structure.

_T__ Atmospheric pressure is lower at high elevations than it is at sea level.

(5 pts.)

  1. Match each term with its definition.

__F__ Pascal / A. The assertion that the tiny particles in all forms of matter are in constant motion
__E__ Boiling point / B. Conversion from Celsius to Kelvin temperature.
__B__ OC + 273.15 / C. Phase change from the solid to the vapor state.
__C__ Sublimation / D. Device for measuring atmospheric pressure.
__A__ Kinetic theory / E. The temperature where the vapor pressure of a substance equals the external pressure
__D__ Barometer / F. SI Unit of gas pressure.

(9 pts.)

  1. Place the following labels on the phase diagram of water below.

a)Regions

i)Solid

ii)Liquid

iii)Vapor

b)Physical Constants

i)Normal melting point

ii)Normal boiling point

iii)Triple point.

c)What phase transitions are represented by the arrows A, B, and C?

101.3

Pressure (kPa)

Normal melting pt.normal boiling pt.

Temperature (oC)

(2 pts.)

  1. Use the graph below to determine the boiling point of water, in Kelvin, at an external pressure of 45 kPa .

353 K

Chemistry Chapter 13 QuizName ______KEY______

  1. What happens to the average kinetic energy of the particles in a sample of matter as the temperature of the sample is increased?

a. It does not change. b. It increases.c. It decreases.

  1. Consider an iron ball and an aluminum ball. If the two balls were at the same temperature, how would the average kinetic energy of the iron atoms compare with the average kinetic energy of the aluminum atoms?
    a. The average kinetic energy of the iron atoms would be greater.
    b. There would be no difference in the average kinetic energies.
    c. The average kinetic energy of the aluminum atoms would be greater.
    d. No determination can be made on the basis of the information given.
  2. Which temperature scale provides a direct measure of the average kinetic energy of a substance?

a. Fahrenheit b. Celsius c. Kelvin

  1. What is the SI unit of pressure?

a. mole b. candela c. Newtond. Pascale. Joule

  1. Which of the following best describes the motion of iron atoms in a piece of steel?

a. All are moving.b. All are at rest. c. A few are moving.

  1. Collisions between gas molecules are _____.

a. never observed b. elasticc. inelastic

  1. The average kinetic energy of water molecules is greatest in _____.

a. water at 373 K b. ice at 0oC c. water at 90oC d. steam at 200oC

  1. According to the kinetic theory of gases _____.
    a. the particles in a gas are far apart
    b. the particles of a gas move independently of each other
    c. the particles in a gas move rapidly
    d. all of the above
  2. The temperature at which the motion of particles theoretically ceases is _____.

a. 273oC b. 0oC c. -273 K d. 0 K

  1. What is the pressure of one standard atmosphere?

a. 0 kPa b. 101 kPac. 10.1 kPa d. 1010 kPa

  1. Standard conditions when working with gases are defined as _____.
    a. 0oC and 10 kPa b. 0 K and 101 kPa

c. 0oC and 101 kPad. 0 K and 10 kPa

  1. The pressure of a gas in a container is 152 mm Hg. This is equivalent to _____.
    a. 0.3 atm b. 0.2 atmc. 0.4 atm d. 2 atm
  1. Why does a liquid's evaporation rate increase when the liquid is heated?
    a. because more surface molecules have enough energy to overcome the attractive forces holding them in the liquid
    b. because the average kinetic energy of the liquid decreases
    c. because the potential energy of the liquid increases
    d. because the surface area of the liquid is reduced
  1. What types of forces exist between particles of a liquid?
    a. strong attractive forces b. strong repulsive forces

c. weak attractive forcesd. weak repulsive forces

  1. What is the pressure when a liquid is boiling at its normal boiling point?

a. 0 kPa b. 505 kPa c. 202 kPa d. 101 kPa

  1. When the vapor pressure of a liquid is equal to the atmospheric pressure, the liquid _____.
    a. condenses b. boils

c. freezes d. No change is observed.

  1. Water could be made to boil at 105oC instead of 100oC by _____.
    a. decreasing the pressure on the water
    b. applying a great deal of heat
    c. increasing the air pressure on the water
    d. decreasing the air pressure above the water
  1. The boiling points of ionic solids tend to be _____.

a. highb. low c. average

  1. Which of the following is NOT a phase change?

a. melting b. sublimation c. vaporization d. diffusion