Front

What is a balanced chemical equation?

Back

A balanced chemical equation has the same number of each type of atom on both sides of the equation, indicating that mass is conserved during a chemical reaction.

Front

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

Back

To determine the number of atoms in a compound, look at the subscripts in the chemical formula. For example, in H2O, there are 2 hydrogen atoms and 1 oxygen atom.

Front

What does the subscript in a chemical formula represent?

Back

The subscript indicates the number of atoms of the element in the molecule. For example, in Ca(OH)2, the '2' indicates there are 2 hydroxide ions.

Front

How many atoms of O are in H2O?

Back

There is 1 atom of oxygen in H2O.

Front

How many atoms of H are in H2O?

Back

There are 2 atoms of hydrogen in H2O.

Front

What is the total number of atoms in Ca(OH)2?

Back

There are 3 atoms in Ca(OH)2: 1 calcium, 2 oxygen, and 2 hydrogen.

Front

How many atoms of H are in 3Mg(OH)2?

Back

There are 6 atoms of hydrogen in 3Mg(OH)2.

Front

What is the purpose of balancing a chemical equation?

Back

The purpose of balancing a chemical equation is to ensure that the law of conservation of mass is followed, meaning the same number of each type of atom is present before and after the reaction.

Front

Is the equation HCl + NaOH --> NaCl + H2O balanced?

Back

Yes, the equation is balanced.

Front

How many atoms of Mg are in 3Mg(OH)2?

Back

There are 3 atoms of magnesium in 3Mg(OH)2.