Counting Atoms with Subscripts

How many Oxygen atoms are in the chemical equation?

• 4

• 2

• 8

• 13

Answer explanation

The subscript for Oxygen is affected by the subscript outside the parentheses. Think of it as the distributive property in math.

Tags

NGSS.MS-PS1-1

How many Calcium (Ca) are in the equation?

• 3

• 4

• 2

• 8

Tags

NGSS.MS-PS1-1

• 3

• 8

• 4

• 2

Tags

NGSS.MS-PS1-1

• 3

• 6

• 2

• 4

Tags

NGSS.MS-PS1-1

How many Hydrogen atoms are in the chemical equation?

• 4

• 2

• 8

• 6

Tags

NGSS.MS-PS1-1

How many atoms are Sulfur (S) in the chemical equation?

• 4

• 2

• 1

• 8

Answer explanation

The subscript only affects the atom it is following UNLESS it is an atom inside parentheses with a subscript on the outside.

Tags

NGSS.MS-PS1-1

How many Nitrogen atoms are in the chemical equation?

• 8

• 4

• 1

• 2

Tags

NGSS.MS-PS1-1

How many Hydrogen atoms are in the chemical equation? ​ (a)  

• 1
• 4
• 8
• 2

Tags

NGSS.MS-PS1-1

Match the following elements to the correct number of each atom shown in the equation.

• O

• 2

• Ba

• 8

• P

• 3

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

Reorder the following atoms from the least amount to the greatest amount according to the chemical equation.

• O

• S

• Fe

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5