Chem 162 Exam Questions and Verified Answers
Which of the following is a Lewis acid?
AlBr3
Determine the initial ammonia concentration of an aqueous solution that has a pH of 11.00. The
equation for the dissociation of NH3 (Kb = 1.8 × 10-5) is NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH-(aq).
0.056 M
Which of the following is most acidic?"
HCl
What is the pH of a buffer solution that is 0.211 M in lactic acid and 0.111 M in
sodium lactate?
3.57
Which of the following species is amphoteric?
HPO42-
When this table is completed correctly, what is Y, the expression for the final pressure
of hydrogen?
3.2-3x
If the Ka of a weak acid is 5.6 x 10-11, then the Kb of the conjugate base is?
1.8 x 10-4
Classify the type of electrolyte: CH3OH(l) → CH3OH(aq)
, Non electrolyte
What is the molar mass of a gas that has a density of 0.179 g/L at STP?
4 (conversion factor 22.4L/mol)
The pressure of a gas is 1.10 atm. What is its pressure in mmHg?
836 (1 atm = 760 mm Hg or torr)
Classify the type of electrolyte: HF(g) ↔ H+(aq) + F-(aq)
weak
A gas mixture containing oxygen, nitrogen, and neon exerts a total pressure of 600mmHg. If
the partial pressure of nitrogen is 210mmHg and partial pressure of neon is 100mmHg,
what is the partial pressure of oxygen?
290 (600-210-100=290)
The density of (1 mol) C3H8 gas at STP is:
1.96 (Molar mass /Molar volume) Molar vol = 22.4L/mol
The numerical value for the gas constant in mmHg, liters, Kelvins, and moles is:
0.08206
At STP, 12.69 g of a noble gas occupies 14.09 L. What is the identity of the noble gas?
Ne (molar mass*specific volume(X)= molar volume at the temperature given(V)) (X= g/L)
6.0L of a gas having pressure of 650mmHg will have a volume of ________ when it's pressure
is 1.1atm.
4.7 (Boyles law PV1=PV2)
What is the molar mass of 3.93 g of a gas that occupies 2.00L at STP?
44 ( 1mol/22.4L)
Which of the following is a Lewis acid?
AlBr3
Determine the initial ammonia concentration of an aqueous solution that has a pH of 11.00. The
equation for the dissociation of NH3 (Kb = 1.8 × 10-5) is NH3(aq) + H2O(l) ⇌ NH4+(aq) + OH-(aq).
0.056 M
Which of the following is most acidic?"
HCl
What is the pH of a buffer solution that is 0.211 M in lactic acid and 0.111 M in
sodium lactate?
3.57
Which of the following species is amphoteric?
HPO42-
When this table is completed correctly, what is Y, the expression for the final pressure
of hydrogen?
3.2-3x
If the Ka of a weak acid is 5.6 x 10-11, then the Kb of the conjugate base is?
1.8 x 10-4
Classify the type of electrolyte: CH3OH(l) → CH3OH(aq)
, Non electrolyte
What is the molar mass of a gas that has a density of 0.179 g/L at STP?
4 (conversion factor 22.4L/mol)
The pressure of a gas is 1.10 atm. What is its pressure in mmHg?
836 (1 atm = 760 mm Hg or torr)
Classify the type of electrolyte: HF(g) ↔ H+(aq) + F-(aq)
weak
A gas mixture containing oxygen, nitrogen, and neon exerts a total pressure of 600mmHg. If
the partial pressure of nitrogen is 210mmHg and partial pressure of neon is 100mmHg,
what is the partial pressure of oxygen?
290 (600-210-100=290)
The density of (1 mol) C3H8 gas at STP is:
1.96 (Molar mass /Molar volume) Molar vol = 22.4L/mol
The numerical value for the gas constant in mmHg, liters, Kelvins, and moles is:
0.08206
At STP, 12.69 g of a noble gas occupies 14.09 L. What is the identity of the noble gas?
Ne (molar mass*specific volume(X)= molar volume at the temperature given(V)) (X= g/L)
6.0L of a gas having pressure of 650mmHg will have a volume of ________ when it's pressure
is 1.1atm.
4.7 (Boyles law PV1=PV2)
What is the molar mass of 3.93 g of a gas that occupies 2.00L at STP?
44 ( 1mol/22.4L)
