Balancing Chemical Equations

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 the reaction.

Front

What is an unbalanced chemical equation?

Back

An unbalanced chemical equation does not have the same number of each type of atom on both sides, meaning that mass is not conserved.

Front

How do you determine if a chemical equation is balanced?

Back

Count the number of atoms of each element on both sides of the equation. If they are equal, the equation is balanced.

Front

What is the law of conservation of mass?

Back

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction; it can only change forms.

Front

What does the coefficient in a chemical equation represent?

Back

The coefficient indicates the number of molecules or moles of a substance involved in the reaction.

Front

What is the role of subscripts in a chemical formula?

Back

Subscripts indicate the number of atoms of each element in a molecule. For example, in H2O, the '2' indicates there are two hydrogen atoms.

Front

What is the first step in balancing a chemical equation?

Back

Identify the number of atoms of each element in the reactants and products.

Front

What is a common mistake when balancing equations?

Back

A common mistake is to change the subscripts of compounds instead of adjusting the coefficients.

Front

What is the balanced equation for the combustion of propane (C3H8)?

Back

C3H8 + 5 O2 → 3 CO2 + 4 H2O.

Front

What is the balanced equation for the reaction of sodium (Na) with chlorine (Cl2)?

Back

2 Na + Cl2 → 2 NaCl.