Just Balancing Equations

Front

What is a coefficient in a chemical equation?

Back

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

Front

What is a reactant in a chemical equation?

Back

A reactant is a substance that undergoes a chemical change in a reaction, found on the left side of the equation.

Front

What are products in a chemical equation?

Back

Products are the substances formed as a result of a chemical reaction, found on the right side of the equation.

Front

What does the law of conservation of mass state?

Back

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction; the total mass of reactants equals the total mass of products.

Front

In the equation CH4 + 2 O2 → CO2 + 2 H2O, what are the reactants?

Back

The reactants are CH4 (methane) and O2 (oxygen).

Front

In the equation Mg + ___ HCl → MgCl2 + H2, how many HCl molecules are needed?

Back

2 HCl molecules are needed.

Front

What is the purpose of balancing a chemical equation?

Back

The purpose of balancing a chemical equation is to ensure that the number of atoms for each element is the same on both sides of the equation, adhering to the law of conservation of mass.

Front

What is a subscript in a chemical formula?

Back

A subscript is a number written below and to the right of a chemical symbol that indicates the number of atoms of that element in a molecule.

Front

What is the difference between a coefficient and a subscript?

Back

A coefficient indicates the number of molecules, while a subscript indicates the number of atoms in a molecule.

Front

What does it mean if a chemical equation is unbalanced?

Back

An unbalanced chemical equation does not have the same number of atoms of each element on both sides, violating the law of conservation of mass.