Chemistry Unit Review - Part 4: 8.P.1.4

• Add the coefficient 2 before the Mg on both sides of the equation.

• Add the coefficient 2 before the Mg on the left side of the equation.

• Add the coefficient 2 before the MgO on the right side of the equation.

• 1 gram

• 7 grams

• 19 grams

Which BEST represents a balanced equation?

• L

• 1

• 2

• 4

• 8

• The hydrogen and oxygen molecules combine to form water.

• Hydrogen and oxygen are held together by strong chemical bonds.

• There are hydrogen and oxygen atoms on both sides of the equation.

• The same number of hydrogen and oxygen atoms are on both sides of the equation.

A chemistry student combines 32 grams of one chemical and an unknown amount of another chemical in a closed system. A chemical reaction occurs and the mass of the products is 114 grams. How much of the unknown chemical was used in the reaction?

• 32 grams

• 82 grams

• 114 grams

What is the importance of a closed container in a chemical reaction?

• to observe the mass before and after the reaction occurs

• to keep any materials from interfering with the reaction

• to observe the loss of mass after the reaction occurs

Which BEST represents a balanced equation?