CHEM | LESSON 2

Question 1

one or more reactants is converted to one or more products.

Answer 1

Chemical reaction

Question 2

alters the physical state of a substance without changing its composition.

Answer 2

Physical change

Question 3

a chemical reaction) converts one substance into another.

Answer 3

Chemical change

Question 4

Chemical reactions involve:

Answer 4

Breaking bonds in the reactants (starting materials)
Forming new bonds in the products

Question 5

Burning in air

Answer 5

Combustion

Question 6

The loss of electrons.

Answer 6

Oxidation

Question 7

The loss of electrons.

Answer 7

Reduction

Question 8

Any reaction in which electrons are transferred from one species to another.

Answer 8

Oxidation-reduction redox reaction

Question 9

The gain of oxygen and/or loss of hydrogen.

Answer 9

Oxidation

Question 10

The gain of oxygen and/or loss of hydrogen.

Answer 10

Reduction

Question 11

The process by which living organisms use O2 to oxidize carbon- containing compounds to produce CO2 and H2O. The importance of these reactions is not the CO2 produced, but the energy released.

Answer 11

Respiration

Question 12

The oxidation of iron to a mixture of iron oxides

Answer 12

Rusting

Question 13

The oxidation of colored compounds to products which are colorless.

Answer 13

Bleaching

Question 14

In all cases, the reaction taking place in a battery is a redox reaction.

Answer 14

Batteries

Question 15

The sum of the atomic weights in atomic
mass units (amu) of all atoms in a compound’s formula.

Answer 15

Formula weight

Question 16

can be used for both ionic and molecular compounds; it tells nothing about whether a compound is ionic or molecular.

Answer 16

Formula weight

Question 17

should be used only for molecular compounds.

Answer 17

Molecular weight

Question 18

The amount of substance that contains as many atoms, molecules,
or ions as there are atoms in exactly 12 g of carbon-12.

Answer 18

Mole

Question 19

The number of formula units in a mole is known as

Answer 19

Avogadro’s number

Question 20

The number of formula units in a mole is known as

Answer 20

6.02214199 x 10^23

Question 21

The formula weight of a substance expressed
in grams.

Answer 21

Molar mass

Question 22

The study of mass relationships in chemical
reactions.

Answer 22

Stoichiometry

Question 23

The reagent that is used up first in a
chemical reaction.

Answer 23

Limiting reagent

Question 24

The mass of product formed in a chemical
reaction and recovered in the laboratory.

Answer 24

Actual yield

Question 25

The mass of product that should form according to the stoichiometry of the balanced chemical equation.

Answer 25

Theoretical yield

Question 26

Actual yield divided by theoretical yield times 100..

Answer 26

Percent yield