Chapter 19

Question 1

a change in which one or more reactants are converted to a new product/substance

Answer 1

chemical reaction

Question 2

initial substances in a chemical reaction

Answer 2

reactants

Question 3

new substances produced as a result of chemical reaction

Answer 3

products

Question 4

a shorthand form of expressing chemical reactions using chemical formulas and other symbols

Answer 4

chemical equation

Question 5

balanced chemical equation

Answer 5

a chemical equation with the same number of atoms on both sides

Question 6

why do chemists use elements in grams instead of amu

Answer 6

it’s virtually impossible to select individual atoms of an element. so, the ratios remain the same, but the elements involved are measured in grams.

Question 7

the amount of a substance containing 6.02 × 10^23 particles of said substance

Answer 7

mole

Question 8

why are moles measured calculated with the number 6.02 × 10^23?

Answer 8

sizing up atom portions but keeping the ratios intact causes all elements to be multiplied by the same amount; in this case, by 6.02 x 10^23

Question 9

the mass in grams of one mole of a substance

Answer 9

molar mass

Question 10

what is true about amu and molar mass

Answer 10

they will have the same numeric measurement, but their units will be different

Question 11

what can you use molar mass to calculate

Answer 11

number of moles and mass

Question 12

a reaction that occurs when a substance reacts with oxygen to produce thermal and light energy

Answer 12

combustion reaction

Question 13

a reaction where two or more substances combine to form another substance

Answer 13

synthesis reaction

Question 14

what is the generalized formula for synthesis reactions

Answer 14

A + B = AB

Question 15

reactions that occur when one substance breaks down, or decomposes, into two or more substances

Answer 15

decomposition reactions

Question 16

what is the general formula for decomposition reactions

Answer 16

AB => A + B

Question 17

c/c decomposition reactions and synthesis reactions

Answer 17

they are complete opposites of each other

Question 18

the chemical reaction in which one element replaces another element in a compound

Answer 18

single-displacement reaction

Question 19

generalized equation for single-displacement reactions

Answer 19

A + BC => AC + B

Question 20

a reaction where the positive ion of one compounds replaces the positive ion of the other to form two new compounds

Answer 20

double-displacement reaction

Question 21

generalized equation for double-displacement reaction

Answer 21

AB + CD => AD + CB

Question 22

c/c single-displacement and double-displacement reactions

Answer 22

single-displacement: one element displaced by another element (AB + C = AC + B)
double-displacement: ions replace each other and one element of each compound is displaced
(AB + CD = AD + CB)

Question 23

an insoluble compound that comes out of a solution from a double-displacement reaction

Answer 23

precipitate

Question 24

the loss of electrons during a chemical reaction

Answer 24

oxidation

Question 25

the gain of electrons during a chemical reaction

Answer 25

reduction

Question 26

c/c oxidation and reduction

Answer 26

oxidation: lose electrons reduction: gain electrons always come as a pair

Question 27

nickname for the pair that is reduction and oxidation

Answer 27

redox

Question 28

chemical reactions that release energy

Answer 28

exergonic reaction

Question 29

the rate at which chemical reactions take place

Answer 29

reaction rate

Question 30

a ‘commonsense’ idea that explains why reaction rates depend upon external factors; states that atoms, ions, and molecules must collide in order to react

Answer 30

collision model

Question 31

why does the collision model matter (in terms of its relations to reaction rate)

Answer 31

it explains why reaction rates may change according to external factors, including temperature, concentration, volume and pressure, and surface area.

Question 32

a substance that speeds up a chemical reaction

Answer 32

catalyst

Question 33

a substance that slows the rates of chemical reactions

Answer 33

inhibitor

Question 34

a reaction that can occur in both the forward and reverse directions (product => reactant => product)

Answer 34

reversible reaction

Question 35

equilibrium

Answer 35

a state in which forward and reverse reactions/processes proceed at equal rates

Question 36

the principle that states that if a stress is applied to a system at equilibrium, the equilibrium shifts in the direction that opposes the stress.

Answer 36

Le Châtelier’s principle

Question 37

exergonic reaction that primarily releases thermal energy

Answer 37

exothermic reaction

Question 38

chemical reaction where energy is absorbed; such reactions require more energy to break bonds than is released from formation of new bonds

Answer 38

endergonic reaction

Question 39

endergonic reaction that primarily requires/absorbs thermal energy in order to continue

Answer 39

endothermic reaction

Question 40

c/c endothermic and exothermic reactions

Answer 40

exothermic: release thermal energy endothermic: absorb thermal energy

Question 41

c/c endergonic and exergonic reactions

Answer 41

exergonic: energy released from bonding > energy required to break bonds; energy released endergonic: energy required to break bonds > energy released from bonding; energy absorbed