Question 1

Highway road crews sometimes spread salt on icy roads during the winter because the solution process generates heat, which melts the ice.

Accepted Answer

A) True 
 B)False  False

Question 2

The following aqueous solutions, with one mole of each solid in equal volumes of water are prepared.
C6H12O6(s) $\rightarrow$ C6H12O6(aq)
NaNO3(s) $\rightarrow$ Na+(aq) + NO3-(aq)
CaCl2 (aq) $\rightarrow$ Ca2+(aq) + 2Cl-(aq)
Which solution would have the lowest freezing point?

Accepted Answer

A)   C6H12O6
B)   NaNO3
C)   CaCl2
D)   All of the responses would have the same freezing point.  C

Question 3

How many molecules are in an 8.0 g sample of oxygen gas, O2?

Accepted Answer

A)   6.0 × 1023
B)   3.0 × 1023
C)   1.5 × 1023
D)   12.0 × 1023 C

Question 4

What is the number of atoms on each side of the equation, CH4 + 2O2 $\rightarrow$ CO2 + 2H2O?

Accepted Answer

A)   5
B)   6
C)   7
D)   9

Question 5

What is the total mass of products in the methane reaction CH4 + 2O2 $\rightarrow$ CO2 + 2H2O?

Accepted Answer

A)   80 u
B)   64 u
C)   62 u
D)   48 u

Question 6

One mole of particles lowers the freezing point of 1,000 g of water by 1.76ºC. What is the freezing point of a solution containing one mole of NaNO3 in 1,000 g of water?

Accepted Answer

A)   30.24ºC
B)   28.48ºC
C)   ?1.76ºC
D)   ?3.52ºC

Question 7

What is the mass percent of sodium in washing soda, Na2CO3?

Accepted Answer

A)   43.4%
B)   32.5%
C)   21.7%
D)   62.1%

Exam 3: Chemical Reactions, Water and Solutions

Highway road crews sometimes spread salt on icy roads during the winter because the solution process generates heat, which melts the ice.

How many molecules are in an 8.0 g sample of oxygen gas, O₂?

What is the number of atoms on each side of the equation, CH₄ + 2O₂ $\rightarrow$ CO₂ + 2H₂O?

What is the total mass of products in the methane reaction CH₄ + 2O₂ $\rightarrow$ CO₂ + 2H₂O?

One mole of particles lowers the freezing point of 1,000 g of water by 1.76ºC. What is the freezing point of a solution containing one mole of NaNO₃ in 1,000 g of water?

What is the mass percent of sodium in washing soda, Na₂CO₃?

Exam 3: Chemical Reactions, Water and Solutions

Highway road crews sometimes spread salt on icy roads during the winter because the solution process generates heat, which melts the ice.

The following aqueous solutions, with one mole of each solid in equal volumes of water are prepared. C6H12O6(s) →\rightarrow→ C6H12O6(aq) NaNO3(s) →\rightarrow→ Na+(aq) + NO3-(aq) CaCl2 (aq) →\rightarrow→ Ca2+(aq) + 2Cl-(aq) Which solution would have the lowest freezing point?

How many molecules are in an 8.0 g sample of oxygen gas, O2?

What is the number of atoms on each side of the equation, CH4 + 2O2 →\rightarrow→ CO2 + 2H2O?

What is the total mass of products in the methane reaction CH4 + 2O2 →\rightarrow→ CO2 + 2H2O?

One mole of particles lowers the freezing point of 1,000 g of water by 1.76ºC. What is the freezing point of a solution containing one mole of NaNO3 in 1,000 g of water?

What is the mass percent of sodium in washing soda, Na2CO3?

How many molecules are in an 8.0 g sample of oxygen gas, O₂?

What is the number of atoms on each side of the equation, CH₄ + 2O₂ $\rightarrow$ CO₂ + 2H₂O?

What is the total mass of products in the methane reaction CH₄ + 2O₂ $\rightarrow$ CO₂ + 2H₂O?

One mole of particles lowers the freezing point of 1,000 g of water by 1.76ºC. What is the freezing point of a solution containing one mole of NaNO₃ in 1,000 g of water?

What is the mass percent of sodium in washing soda, Na₂CO₃?