5 Steps to a 5 AP Chemistry

20  STEP 2. Determine Your Test Readiness

19.The volume and pressure of a real gas are not the
same as those calculated from the ideal gas equa-
tion, because the ideal gas equation does NOT
take into account:

(A) the attraction between the molecules and the

speed at which the molecules are moving

(B) the volume of the molecules and the mass of

the molecules

(C) the attraction between the molecules and

the mass of the molecules

(D) the volume of the molecules and variations

in the absolute temperature

(E) the volume of the molecules and the attrac-

tion between the molecules

20.Aluminum metal reacts with HCl to produce alu-
minum chloride and hydrogen gas. What volume
of hydrogen gas, at STP, is produced when 13.5 g
of aluminum is mixed with an excess of HCl?

(A) 22.4 L

(B) 33.6 L

(C) 11.2 L

(D) 16.8 L

(E) 7.47 L

21.A sample containing the gases carbon dioxide,
carbon monoxide, and water vapor was analyzed
and found to contain 4.5 mol of carbon dioxide,
4.0 mol of carbon monoxide, and 1.5 mol of
water vapor. The mixture had a total pressure of
1.2 atm. What was the partial pressure of the
carbon monoxide?

(A) 0.48 atm

(B) 0.18 atm

(C) 5.4 atm

(D) 0.54 atm

(E) 0.98 atm

22.An ideal gas sample weighing 0.548 g at 100°C
and 0.993 atm has a volume of 0.237 L. Determine
the molar mass of the gas.

(A) 71.3 g/mol

(B) 143 g/mol

(C) 19.1 g/mol

(D) 0.0140 g/mol

(E) 35.7 g/mol

23.If a sample of He effuses at a rate of 30 mol per

hour at 45°C, which of the gases below will effuse

at approximately one-half the rate under the same

conditions?

(A) CH 4

(B) O 3

(C) N 2

(D) H 2

(E) CO

Chapter 9

Choose from the following types of energy for

questions 24–27.

(A) free energy

(B) lattice energy

(C) kinetic energy

(D) activation energy

(E) ionization energy

24.The energy required to produce a gaseous cation

from a gaseous atom in the ground state

25.The average ____________ is the same for any

ideal gas at a given temperature.

26.The maximum energy available for useful work

from a spontaneous reaction

27.The energy required to completely separate the

ions from a solid is

28.Oxidation of ClF by F 2 yields ClF 3 , an important

fluorinating agent formerly used to produce the

uranium compounds in nuclear fuels: ClF(g) +

F 2 (g)→ ClF 3 (l). Use the following thermochem-

ical equations to calculate ΔH°rxnfor the produc-

tion of ClF 3 :

1. 2 ClF(g) +O 2 (g) ΔH°=167.5 kJ
   → Cl 2 O(g) +OF 2 (g)


2. 2 F 2 (g) +O 2 (g) ΔH°=−43.5 kJ
   → 2 OF 2 (g)


3. 2 ClF 3 (l) +2 O 2 (g) ΔH°=394.1 kJ
   → Cl 2 O(g) +3 OF 2 (g)

(A) +270.2 kJ

(B) −135.1 kJ

(C) 0.0 kJ

(D) −270.2 kJ

(E) +135.1 kJ