Chapter 5 Chemistry Calculations

Question 1

Mole

Answer 1

A group of atoms, molecules, or formula units that contains 6.022 *10^23^ of these items.

Question 2

Molar mass

Answer 2

The mass in grams of 1 mole of an element is equal numerically to its atomic mass. The molar mass of a compound is equal to the sum of the masses of the elements in the formula.

Question 3

Avogadro’s number

Answer 3

The number of items in a mole , equal to 6.02 * 10^23^.

Question 4

Balanced equation

Answer 4

The final form of a chemical reaction that shows the same number of atoms of each element in the reactants and products.

Question 5

Chemical equation

Answer 5

A shorthand way to represent a chemical reaction using chemical formulas to indicate the reactants and products.

Question 6

Chemical reaction

Answer 6

The process by which a chemical change takes places

Question 7

Chemical change

Answer 7

The formation of a new substance with a different composition and properties than the initial substance.

Question 8

Coefficients

Answer 8

Whole numbers placed in front of the formulas in an equation to balance the number of atoms of each element.

Question 9

Combination reaction

Answer 9

A reaction in which reactants combine to form a single product.

Question 10

Combustion reaction

Answer 10

A reaction in which an element or a compound reacts with oxygen to form oxide products.
Normally a fuel + oxygen gas –> carbon dioxide + water.

Question 11

Decomposition reaction

Answer 11

A reaction in which a single reactant splits into two or more simpler substances.

Question 12

Double displacement (replacement) reaction

Answer 12

A reaction in which parts of two different reactants exchange places.
Normally compound + compound –> compound + compound

Question 13

Single displacement (replacement) reaction

Answer 13

A reaction in which an element replaces a different element in a compound.
Normally element + compound –> element + compound.

Question 14

Reactants

Answer 14

The initial substances that undergo change in a chemical reaction.

Question 15

Products

Answer 15

The substances formed as a result of a chemical reaction.

Question 16

Law of conservation of mass

Answer 16

In a chemical reaction, the total mass of the total mass of the reactants is equal to the total mass of the product: matter is neither lost nor gained.

Question 17

Mole-mole factor

Answer 17

A conversion factor that relates the number of moles to two compounds in and equation derived from their coefficient.

Question 18

Percent yield

Answer 18

The ratio of the actual yield of a reaction to the theoretical yield possible for the reaction.

Question 19

Theoretical yield

Answer 19

The maximum amount o product that a reaction can produce form a given amount of reactant.