Free Printable The Mole, Stoichiometry and Reactions Rates

Worksheets

The Mole, Stoichiometry and Reactions Rates

Total questions: 22

Worksheet time: 47mins

Name

Class

Date

Determine the molar mass for carbon tetrachoride

153.823 g/mol

118.37 g/mol

189.35 g/mol

47.464 g/mol

How many moles are in 19.82 g Mg?

1.226mol Mg

481.7mol Mg

1.000mol Mg

0.8156 mol Mg

How many grams is 1.2 moles of Neon?

0.05 grams

16.6 grams

21.2 grams

24 grams

(0904) How many molecules are present in 25 g of O₂?

32. molecules

0.78 molecules

4.7x10²³ molecules

1.3 x 10²³ molecules

2 C₂H₆ + 7 O₂ → 4 CO₂ + 6 H₂O

Ethane (C₂H₆) combusts in the above reaction. What is the mole ratio of ethane to oxygen gas?

2 C₂H₆ + 7 O₂ → 4 CO₂ + 6 H₂O

New problem: If 16 moles of carbon dioxide are formed by this reaction, how many moles of water were also produced?

4 mol H₂O

6 mol H₂O

24 mol H₂O

96 mol H₂O

384 mol H₂O

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

6.7 mol

1.0 mol

10.1 mol

4.5 mol

CH₄ + 2 O₂ → CO₂ + 2 H₂O
How many moles of carbon dioxide are produced from the combustion of 110 g of CH₄?

13.7 mol

2.75 mol

6.11 mol

6.85 mol

2Na + 2H₂O → 2NaOH+ H₂
How many grams of hydrogen are produced if 120 g of Na are available?

5.2 g

2.6 g

690 g

45 g

10.

What is the percentage of chlorine in sodium chloride? (NaCl)

60.7%

39.3%

60%

40%

11.

You are given the following percentages: 40.05 g S and 59.95 g O. Find the empirical formula for these elements.

SO2

SO3

SO4

12.

The rate of a chemical reaction is NOT affected by which of the following:

temperature

concentration

particle size (surface area)

All of these affect reaction rates

13.

A ______________ is a substance that increases the rate of a reaction without being used up during the reaction.

catalyst

product

reactant

solute

14.

Products will form faster if____________

the particle size of the reactants are larger.

temperature is decreased.

concentration of the reactants are increased.

the reaction is not stirred.

15.

The rate of a reaction increases as temperature__________________.

Decreases

Increases

Stays the Same

16.

Catalysts permit reactions to proceed along a ___________energy path.

lower

higher

17.

Smaller particle size allows for a _________ surface area to be exposed for the reaction.

larger

smaller

18.

Which of the following will lower the rate

of reaction?

adding an enzyme to the reaction

decreasing the temperature from 40°C to

10°C

breaking a chunk of calcium up into

smaller pieces

increasing the amount of solute

dissolved in a solution

19.

Le Chaltelier's Principle states that if a chemical system at equilibrium is stressed,

the system will adjust to increase the stress

the system will adjust to reduce the stress

the system will not adjust

20.

For the reaction...
SO_2(g) + O_2(g) <−> SO_3(g)
If the concentration of SO_2(g)is increased, the equilibrium of the reaction will ___________.

shift to the left

shift to the right

not shift

21.

For the reaction...
SO_2(g) + O_2(g) <−> SO_3(g)
If the equilibrium shifts to the right, the concentration of O_2(g) will ___________.

increase

decrease

remain the same

22.

For the reaction...
heat + N_2(g) + O_2(g) <−> 2NO_(g)
If the heat is removed to the chemical system, the equilibrium will _______.