Counting Atoms

Front

What are reactants in a chemical equation?

Back

Reactants are the substances that undergo a chemical change in a reaction, found on the left side of the equation.

Front

In the equation 2H₂ + O₂ → 2H₂O, what are the reactants?

Back

2H₂ + O₂

Front

How many oxygen atoms are in Al₂(SO₄)₃?

Back

12

Front

How many oxygen atoms are in H₂O?

Back

1

Front

How many hydrogen atoms are in 4H₂O?

Back

8

Front

What is the total number of atoms in H₂SO₄?

Back

7

Front

What is the coefficient in a chemical equation?

Back

A coefficient is a number placed in front of a chemical formula to indicate how many molecules or atoms are involved in the reaction.

Front

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

Back

Add the number of each type of atom present in the chemical formula.

Front

What does the subscript in a chemical formula indicate?

Back

A subscript indicates the number of atoms of the element in the molecule.

Front

What is the significance of balancing a chemical equation?

Back

Balancing a chemical equation ensures that the law of conservation of mass is followed, meaning the number of atoms of each element is the same on both sides.