Counting Atoms and Molecules

How many Hydrogen are in 4H₂O?

• 6
• 8
• 2
• 4

How many Magnesium are in 10MgCl₂?

• 10
• 5
• 20

How many O's are in Al₂(SO₄)₃

• 4
• 12
• 7
• 24

Number of H in 3(NH₄)₂CrO₄

• 4
• 2
• 8
• 24

How many atoms are there TOTAL in:
H₂SO₄

• 6
• 5
• 7
• 3

How many elements are in C₆H₁₂O₆?

• 1
• 2
• 3
• 4

How many different elements are present in H₂COCH₂

• 5

• 4

• 3

• 2

The ______ are numbers found on the lower right-hand side of an element symbol.

• Coefficient

• Exponent

• Multiplier

• Subscript

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!

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