3.11 Writing and Balancing Chemical Equations

Question 1

Combustion analysis employs a ________ _______, a process in which one or more substances are converted into one or more different ones.

Answer 1

Combustion analysis employs a chemical reaction, a process in which one or more substances are converted into one or more different ones.

Question 2

Compounds form and change through…

Answer 2

Compounds form and change through chemical reactions

Question 3

A ________ _______ is a particular type of chemical reaction in which a substance combines with oxygen to form one or more oxygen-containing compounds.

Answer 3

A combustion reaction is a particular type of chemical reaction in which a substance combines with oxygen to form one or more oxygen-containing compounds.

Question 4

Combustion reactions also emit ____

Answer 4

Combustion reactions also emit heat

Question 5

We use the heat released by the combustion of _____ __ to cook food and to heat our homes.

Answer 5

We use the heat released by the combustion of natural gas to cook food and to heat our homes.

Question 6

We represent a chemical reaction with a _____ _____.

Answer 6

We represent a chemical reaction with a chemical equation.

Question 7

The substances on the left side of the equation are the _______ and the substances on the right side are the ______

Answer 7

The substances on the left side of the equation are the reactants and the substances on the right side are the products

Question 8

Two hydrogen atoms have vanished, again violating mass conservation. To correct these problems—that is, to write an equation that more closely represents what actually happens— we must ______ the equation

Answer 8

Two hydrogen atoms have vanished, again violating mass conservation. To correct these problems—that is, to write an equation that more closely represents what actually happens— we must balance the equation

Question 9

We need to change the ________ (the numbers in front of the chemical formulas), not the _______ (the numbers within the chemical formulas), to ensure that the number of each type of ____ on the left side of the equation is equal to the number on the right side.

Answer 9

We need to change the coefficients (the numbers in front of the chemical formulas), not the subscripts (the numbers within the hemical formulas), to ensure that the number of each type of atom on the left side of the equation is equal to the number on the right side.

Question 10

Then we add coefficients to the reactants and products to balance an equation, we change the number of molecules in the equation but not the _____ of molecules. To balance the equation for the combustion of methane, we put the coefficient 2 before O2 in the reactants, and the coefficient 2 before H2O in the products

Answer 10

Then we add coefficients to the reactants and products to balance an equation, we change the number of molecules in the equation but not the kind of molecules. To balance the equation for the combustion of methane, we put the coefficient 2 before O2 in the reactants, and the coefficient 2 before H2O in the products

Question 11

balancing the atoms in the most complex substances ____ and the atoms in the ____substances (such as pure elements) ____ often makes the process shorter.

Answer 11

balancing the atoms in the most complex substances first and the atoms in the simplest substances (such as pure elements) last often makes the process shorter.