Counting Atoms

1. How many different ELEMENTS are present in H₂COCH₂

• 5

• 4

• 3

• 2

Tags

NGSS.MS-PS1-1

2. Coefficients in chemical formulas...

• Multiply just the first atom

• Add to the subscripts at the end of the molecule

• Multiply elements without subscripts

• Multiply EVERYTHING!

Tags

NGSS.MS-PS1-1

3. 4CF₂Cl₂

• C = 4, F = 4, Cl = 2

• C = 1, F = 8, Cl = 8

• C = 4, F = 8, Cl = 8

• C = 1, F = 4, Cl = 8

Tags

NGSS.MS-PS1-1

4. H₂SO₄

• H = 2, S = 4, O = 4

• H = 2, S = 1, O = 4

• H = 8, S = 4, O = 4

• H = 2, SO = 4

Tags

NGSS.MS-PS1-1

How many different elements are present in this molecule?

3 NH₄C₂H₃O₂

• 15

• 36

• 5

• 4

Tags

NGSS.MS-PS1-1

A ______ is a number written in front of a chemical formula.

• Coefficient

• Subscript

• Exponent

• Coordinator

How many Hydrogen atoms are in 4H₂O?

• 6

• 8

• 2

• 4

Tags

NGSS.MS-PS1-1

Coefficients tell the number of __________ in a formula.

• Molecules

• Atoms

• Elements

• Oxygen

Tags

NGSS.MS-PS1-1

What does the number 4 represent in 4NH₃?

• Subscript

• Superscript

• Coefficient