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 does the law of conservation of mass state?

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 is a coefficient in a chemical equation?

Back

A coefficient is a number placed in front of a chemical formula in an equation to indicate how many molecules or moles of that substance are involved in the reaction.

Front

How do you balance a chemical equation?

Back

To balance a chemical equation, adjust the coefficients of the reactants and products until the number of atoms of each element is the same on both sides.

Front

What is the purpose of balancing chemical equations?

Back

The purpose of balancing chemical equations is to ensure that the reaction obeys the law of conservation of mass and accurately represents the quantities of reactants and products.

Front

What is the balanced equation for the reaction of magnesium and hydrochloric acid?

Back

Mg + 2 HCl → MgCl2 + H2.

Front

How many HCl molecules are needed to balance the equation: Mg + __ HCl → MgCl2 + H2?

Back

2 HCl molecules are needed to balance the equation.

Front

What is the balanced equation for the synthesis of ammonia from nitrogen and hydrogen?

Back

N2 + 3 H2 → 2 NH3.

Front

What is the balanced equation for the reaction of aluminum and hydrochloric acid?

Back

2 Al + 6 HCl → 3 H2 + 2 AlCl3.

Front

What is the balanced equation for the reaction of zinc and hydrochloric acid?

Back

Zn + 2 HCl → ZnCl2 + H2.