Understanding Chemical Formulas

How can you tell if a new element is present in a chemical formula?

• A new lowercase letter appears.

• A new capital letter appears.

• A number appears before a letter.

• A number appears after a letter.

What does the large number in front of a chemical formula tell you?

• The number of atoms of the first element.

• The number of molecules.

• The number of different elements.

• The total number of atoms in the formula.

What does the small number written below and after an element symbol in a chemical formula tell you?

• The total number of molecules.

• The number of different elements.

• The number of atoms for the element before it.

• The total number of atoms in the formula.

In the chemical formula 5 H2O, how many hydrogen atoms are there in total?

• 2

• 5

• 10

• 1

In the chemical formula Ca(OH)2, how many oxygen atoms are there?

• 1

• 2

• 3

• 4