Understanding Chemistry Laws and Calculations

Fill in the blank: When carbon burns in oxygen to form carbon dioxide, 6 g of carbon combines with ___ g of oxygen.

• 12

• 16

• 22

• 32

According to the laws of chemistry, what is the total mass of reactants equal to?

• Total mass of products

• Half the mass of products

• Double the mass of products

• None of the above.

Fill in the blank: 12 g of carbon will combine with ___ g of oxygen to form carbon dioxide.

• 16

• 22

• 32

• 44

Fill in the blank: 16 g of oxygen reacts with 64 g of copper, so ___ g of oxygen will react with 32 g of copper.

• 4

• 8

• 12

• 16

What mass of copper(II) oxide will be formed from 32 g of copper and 8 g of oxygen?

• 20 g

• 30 g

• 40 g

• 50 g

Fill in the blank: 64 g of copper and 16 g of oxygen give 80 g of copper(II) oxide, so 6.4 g of copper and ___ g of oxygen will give 8 g of copper(II) oxide.

• 1.6

• 2.0

• 2.4

• 3.2

What is the ratio of carbon to oxygen when forming carbon dioxide?

• 1:2

• 1:3

• 1:4

• 1:5

Fill in the blank: The total mass of reactants is equal to the total mass of ___.

• A) Reactants

• B) Products

• C) Elements

• D) Compounds

What is the mass of oxygen needed to react with 6 g of carbon?

• 12 g

• 16 g

• 22 g

• 32 g

What is the full amount of anything in percentage?

• 50%

• 75%

• 100%

• 25%