Chapter 3 - Basics

Question 1

thermodynamics

Answer 1

study of energetics of chemical rxns

Question 2

first law of thermodynamics

Answer 2

• conservation of energy

- energy in universe is constant

Question 3

second law of thermodynamics

Answer 3

• entropy

- entropy of universe tends to increase

Question 4

spontaneous rxns tend to ____ the disorder of the universe

Answer 4

increase

Question 5

favorable rxns are _____ and non-favorable are _____

Answer 5

spontaneous & non-spontaneous

Question 6

spontaneous rxns occur without _____

Answer 6

addition of net energy

Question 7

exergonic rxns

Answer 7

spontaneous

Question 8

endergonic rxns

Answer 8

non-spontaneous

Question 9

difference between Keq and Q

Answer 9

Keq is ratio of products over reactants at equilibrium, while Q is at any given point

Question 10

equilibrium

Answer 10

• point where rate of forward & reverse rxns are equal

- concentrations stay the same

Question 11

addition of a reactant or product causes change in ____

Answer 11

Q

Question 12

chemical kinetics

Answer 12

• study of rxn rates

- all rxns proceed through an unstable transition state

Question 13

activation energy

Answer 13

energy required to produce transition state

Question 14

catalyst

Answer 14

• lowers activation energy w/o changing G
• stabilizes transition state
• not consumed, regenerated

Question 15

enzymes

Answer 15

• biological catalysts

- kinetic role, not thermodynamic role

Question 16

photosynthesis

Answer 16

process by which plants store energy from the sun in the bond energy of carbohydrates

Question 17

plants are ____

Answer 17

photoautotrophs

Question 18

humans are ____

Answer 18

chemoheterotrophs

Question 19

ATP is used to ____

Answer 19

drive energetically unfavorable rxns in cells

Question 20

oxidation

Answer 20

• gain oxygen atoms
• lose hydrogen atoms
• lose electrons

Question 21

reduction

Answer 21

• lose oxygen atoms
• gain hydrogen atoms
• gain electrons

Question 22

redox pair

Answer 22

• if one molecule gets reduced, another gets oxidized

- vice versa

Question 23

catabolism

Answer 23

• break down of molecules

- generally oxidative

Question 24

anabolism

Answer 24

• build up molecules

- generally reductive

Question 25

bronsted-lowery acids & bases

Answer 25

- acids are proton donors | - bases are proton acceptors

Question 26

lewis acids & bases

Answer 26

- acids are electron pair acceptors | - bases are electron pair donors

Question 27

lewis acid/base rxns usually result in _____

Answer 27

coordinate covalent bonds

Question 28

large Ka/Kb value means

Answer 28

strong acid/base

Question 29

small pKa/pKb value means

Answer 29

strong acid/base

Question 30

polyprotic

Answer 30

more than one proton to donate

Question 31

amphoteric

Answer 31

can act as an acid or base

Question 32

what is always amphoteric?

Answer 32

conjugate base of a weak polyprotic acid

Question 33

buffer solution

Answer 33

resists changing pH when small amount of acid or base is added