Test 5 study

Question 1

Chemical Reactions

Answer 1

Chemical changes resulting from a collision between atoms or molecules

Question 2

Reactants

Answer 2

The original substance that undergoes a chemical reaction

Question 3

Products

Answer 3

New substance produced by the reaction

Question 4

Chemical Equation

Answer 4

Expression that uses chemical symbols to represent a chemical reaction

Question 5

Coefficient

Answer 5

Indicates how many molecules or formula units of that substance are involved in the reaction

Question 6

Law of Conservation of mass

Answer 6

States that the total mass of the reactants is equal to the total mass of the products

Question 7

Balanced

Answer 7

Chemical equation that has the same number of each type of atom on each side of the arrow

Question 8

First law of thermodynamics

Answer 8

Controls energy changes in chemical reactions

Question 9

Exothermic reaction

Answer 9

Chemical reaction that releases thermal energy

Question 10

Endothermic reaction

Answer 10

Cause thermal energy to be absorbed and stored in the chemical bonds of the products

Question 11

Second law of thermodynamics

Answer 11

Every chemical reaction must cause a decrease in usable energy and an increase in entropy.

Question 12

Spontaneous

Answer 12

able to occur by itself without continuing outside help.

Question 13

5 main factors that affect the rate of a chemical reaction

Answer 13

1 activation energy
2 temperature
3 concentration
4 Surface area
5 catalyst

Question 14

Activation energy

Answer 14

The kinetic energy necessary for molecules to chemically react

Question 15

Temperature

Answer 15

Increasing temperature will usually speed up a chemical reaction

Question 16

Concentration

Answer 16

Increasing concentration increases the rate of a reaction.

Question 17

Combustion

Answer 17

Reaction of a fuel with oxygen

Question 18

Surface area

Answer 18

Increasing the surface area of the reactants increases the reactant rate

Question 19

Catalyst

Answer 19

Substance that alters that rate of a chemical reaction without being permanently changed in the reaction

Question 20

Chemical equilibrium

Answer 20

If bothe reactions occur at the same rate

Question 21

Le Chatelier’s principle

Answer 21

When equilibrium is disturbed, the system will react to at least partially offset the disturbance

Question 22

Combination Reactions

Answer 22

Chemical reaction in which 2 or more substances combine to form a third substance
A+B=AB

Question 23

Decomposition Reaction

Answer 23

A compound breaks down to form different substances

Question 24

Single-displacement reaction

Answer 24

An element in a reaction is replace by another

Question 25

Double-displacement reaction

Answer 25

Two compounds exchange atoms or ions

Question 26

Salts

Answer 26

ionic compound that does not contain a hydrogen ion or hydroxide ion

Question 27

dissociates

Answer 27

breaks apart into its component ions

Question 28

Litmus

Answer 28

natural occurring pigment turns red

Question 29

Acids

Answer 29

Defined as the substances that produce hydrogen cations when dissolved in an aqueous solution

Question 30

bases

Answer 30

Substances that produce hydroxide anions in an aqueous solution

Question 31

Neutral

Answer 31

Substances that are neither acids nor bases

Question 32

pH scale

Answer 32

measure of the concentration of H^3O+ ions in a given solution

Question 33

Oxidized

Answer 33

Atoms losing electrons

Question 34

Reduced

Answer 34

atom gaining electrons

Question 35

Redox Reactions

Answer 35

Reactions in which electrons are transferred between atoms