Counting Atoms and Balancing Equations

Front

What is the Law of Conservation of Mass?

Back

Mass is neither created nor destroyed.

Front

What are the substances called that are present before a chemical reaction?

Back

Reactants.

Front

What is the small number written below an element in a chemical formula?

Back

Subscript.

Front

How many atoms of an element are present in a molecule if the subscript is 3?

Back

3 atoms.

Front

What are the substances called that are produced after a chemical reaction?

Back

Products.

Front

What is the number in front of a compound in a chemical equation called?

Back

Coefficient.

Front

How do you determine the total number of atoms in a compound?

Back

Add the subscripts of all elements in the compound.

Front

What does a balanced chemical equation indicate?

Back

The number of atoms of each element is the same on both sides of the equation.

Front

What is the significance of balancing chemical equations?

Back

It supports the Law of Conservation of Mass.

Front

In the equation 2H2 + O2 -> 2H2O, how many hydrogen atoms are present?

Back

4 hydrogen atoms.