Balancing Equations (Obj 7-1)

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 do coefficients represent in a chemical equation?

Back

Coefficients are numbers placed in front of formulas in a chemical equation to indicate the number of molecules or moles of a substance involved in the reaction.

Front

What is the purpose of balancing chemical equations?

Back

The purpose is to ensure that the law of conservation of mass is obeyed, meaning that the total mass of reactants equals the total mass of products.

Front

What is the difference between a coefficient and a subscript in a chemical formula?

Back

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

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 first step in balancing a chemical equation?

Back

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

Front

What does it mean if an equation is unbalanced?

Back

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

Front

Can you change subscripts when balancing equations?

Back

No, changing subscripts alters the identity of the substance; only coefficients can be changed.

Front

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

Back

C3H8 + 5O2 → 3CO2 + 4H2O.

Front

How many oxygen atoms are present in the products of the reaction: 2H2 + O2 → 2H2O?

Back

There are 2 oxygen atoms in the products.