The Law of Conservation of Mass

Ammonia, a common fertilizer for plants, is made using the Haber process. During this process, nitrogen gas and hydrogen gas react at high temperatures and pressures.

Consider the following reaction:

1 molecule of nitrogen (N₂) reacts with 3 molecules of hydrogen (H₂) to produce some amount of ammonia (NH₃).

To find the amount of ammonia produced, first determine the number of each type of atom in the products.

• 2...6

• 6...2

• 1..3

• 3...1

1 molecule of nitrogen (N₂) reacts with 3 molecules of hydrogen (H₂) to produce some amount of ammonia (NH₃).

During this reaction, how many molecules of ammonia (NH₃) are produced?

• 6

• 2

• 4

• 1

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Consider the same reaction:

2 molecules of ethylene (C₂H₄) react with 1 molecule of oxygen (O₂) to produce some amount of acetaldehyde (C₂H₄O).

During this reaction, how many molecules of acetaldehyde (C₂H₄O) are produced?

• 1

• 2

• 3

• 4

Tags

NGSS.HS-PS1-7

Sulfuryl chloride is a substance used in factories to make chemicals for killing insects. It breaks down over time into sulfur dioxide and chlorine gas.

Consider the following reaction:

Some amount of sulfuryl chloride (SO₂Cl₂) reacts to produce 1 molecule of sulfur dioxide (SO₂) and 1 molecule of chlorine (Cl₂).

During this reaction, how many molecules of sulfuryl chloride (SO₂Cl₂) react?

• 2

• 1

• 3

• 4

Tags

NGSS.HS-PS1-7

Nitrogen dioxide is a gas commonly found in polluted air. It is produced when nitric oxide in the air reacts with oxygen gas.

Consider the following reaction:

2 molecules of nitric oxide (NO) react with 1 molecule of oxygen (O₂) to produce some amount of nitrogen dioxide (NO₂).

During this reaction, how many molecules of nitrogen dioxide (NO₂) are produced?

• 2

• 4

• 6

• 8

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

NGSS.MS-PS1-1

In this chemical equation , CH₄ and 2O₂ are called the...

• Products

• Reactants

• Coefficient

• Subscript

Tags

NGSS.MS-PS1-2

In this chemical equation , CO₂ and 2H₂O are called the...

• Products

• Reactants

• Coefficient

• Subscript

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-1

How many Carbons are in the chemical reaction?

• 2

• 3

• 4

• 5

There are 4 hydrogens in the products of the equation. How many hydrogens would you expect in the reactants?

• 1

• 3

• 4

• 5

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

NGSS.MS-PS1-1

Looking at the reactants, there is _____ molecule(s) of CH₄ and _______ molecule(s) of O₂.

• 1, 1

• 1, 2

• 2, 2

• 2, 4

Tags

NGSS.HS-PS1-7

NGSS.HS-PS1-2