WGU OA EXAM 2026/2027 | COMPLETE OBJECTIVE ASSESSMENT
EXAM PREP | HIGH-YIELD PRACTICE QUESTIONS & CORRECT
ANSWERS | LATEST UPDATE
1. If you were to increase the concentration of aqueous titanium(IV) chloride in
the reaction with magnesium, what effect would this have on the yield of solid
titanium produced?
The yield of solid titanium would remain unchanged.
The yield of solid titanium would become unpredictable.
The yield of solid titanium would likely increase.
The yield of solid titanium would likely decrease.
2. If 5 moles of phosphorus pentachloride react with 3 moles of arsenic
trifluoride, how many moles of phosphorus pentafluoride can be produced,
assuming complete reaction and a balanced equation?
8 moles of phosphorus pentafluoride
5 moles of phosphorus pentafluoride
3 moles of phosphorus pentafluoride
2 moles of phosphorus pentafluoride
3. If the theoretical yield of ammonium chloride (NH4Cl) from the reaction of
3.4 g of ammonia and 2.1 g of hydrochloric acid is calculated to be 1.5 g, what
would be the percent yield based on the actual yield of 1.2 g?
90%
85%
75%
80%
,4. Describe the type of reaction that occurs when calcium chloride reacts with
sodium phosphate.
It is a decomposition reaction.
It is a double displacement reaction.
It is a combustion reaction.
It is a synthesis reaction.
5. At what pressure, in kilopascals, would 61.5 moles of O2 gas be in a 175 L tank
at 17.0°C? Given: 8.314 L*kPa/mol*K
49.7 kPa
69.9 kPa
847 kPa
605 kPa
6. When aqueous calcium chloride and aqueous sodium phosphate are mixed,
solid calcium phosphate, a substance found tooth enamel and bone mineral,
is formed.
acid-base reaction
precipitation reaction
combustion reaction
decomposition reaction
gas evolution reaction
7. Which conditions would be the most suitable for the liquefaction of air?
1000 atm and 300 K
, 1 atm and 100 K
5 atm and 160.37 K
2000 atm and 73.15 K
8. A 25.0 mL sample of 0.15 M silver nitrate, AgNO3, is reacted with a 3.58 g
sample of calcium chloride, CaCl2 (M = 111.0). Which of the following
statements is true?
Silver nitrate is the limiting reactant and calcium nitrate precipitates.
Calcium chloride is the limiting reactant and calcium nitrate
precipitates.
Silver nitrate is the limiting reactant and silver chloride precipitates.
Calcium chloride is the limiting reactant and silver chloride
precipitates.
9. If a laboratory needs to liquefy air for an experiment, which combination of
temperature and pressure should they aim for?
Moderate temperatures and standard pressures
Very low temperatures and high pressures
High temperatures and atmospheric pressure
Room temperature and low pressures
10. The 18 Karat gold consists of 75% gold mixed with other metals. What mass
of gold is present in a 750 g sample of 18 Karat gold?
560 g
1000 g
500. g
EXAM PREP | HIGH-YIELD PRACTICE QUESTIONS & CORRECT
ANSWERS | LATEST UPDATE
1. If you were to increase the concentration of aqueous titanium(IV) chloride in
the reaction with magnesium, what effect would this have on the yield of solid
titanium produced?
The yield of solid titanium would remain unchanged.
The yield of solid titanium would become unpredictable.
The yield of solid titanium would likely increase.
The yield of solid titanium would likely decrease.
2. If 5 moles of phosphorus pentachloride react with 3 moles of arsenic
trifluoride, how many moles of phosphorus pentafluoride can be produced,
assuming complete reaction and a balanced equation?
8 moles of phosphorus pentafluoride
5 moles of phosphorus pentafluoride
3 moles of phosphorus pentafluoride
2 moles of phosphorus pentafluoride
3. If the theoretical yield of ammonium chloride (NH4Cl) from the reaction of
3.4 g of ammonia and 2.1 g of hydrochloric acid is calculated to be 1.5 g, what
would be the percent yield based on the actual yield of 1.2 g?
90%
85%
75%
80%
,4. Describe the type of reaction that occurs when calcium chloride reacts with
sodium phosphate.
It is a decomposition reaction.
It is a double displacement reaction.
It is a combustion reaction.
It is a synthesis reaction.
5. At what pressure, in kilopascals, would 61.5 moles of O2 gas be in a 175 L tank
at 17.0°C? Given: 8.314 L*kPa/mol*K
49.7 kPa
69.9 kPa
847 kPa
605 kPa
6. When aqueous calcium chloride and aqueous sodium phosphate are mixed,
solid calcium phosphate, a substance found tooth enamel and bone mineral,
is formed.
acid-base reaction
precipitation reaction
combustion reaction
decomposition reaction
gas evolution reaction
7. Which conditions would be the most suitable for the liquefaction of air?
1000 atm and 300 K
, 1 atm and 100 K
5 atm and 160.37 K
2000 atm and 73.15 K
8. A 25.0 mL sample of 0.15 M silver nitrate, AgNO3, is reacted with a 3.58 g
sample of calcium chloride, CaCl2 (M = 111.0). Which of the following
statements is true?
Silver nitrate is the limiting reactant and calcium nitrate precipitates.
Calcium chloride is the limiting reactant and calcium nitrate
precipitates.
Silver nitrate is the limiting reactant and silver chloride precipitates.
Calcium chloride is the limiting reactant and silver chloride
precipitates.
9. If a laboratory needs to liquefy air for an experiment, which combination of
temperature and pressure should they aim for?
Moderate temperatures and standard pressures
Very low temperatures and high pressures
High temperatures and atmospheric pressure
Room temperature and low pressures
10. The 18 Karat gold consists of 75% gold mixed with other metals. What mass
of gold is present in a 750 g sample of 18 Karat gold?
560 g
1000 g
500. g
