Chemistry Test 4

Question 1

enthalpy

Answer 1

heat in joules, H

Question 2

Gibbs Free Energy

Answer 2

work in joules, G

Question 3

entropy

Answer 3

disorder in joules, S

Question 4

characteristics of entropy

Answer 4

• gas is greater entropy than that of liquids and solids
• entropy of a larger maor complex molecule is larger
• entropy of ionic solid with a weaker force is larger
• entropy of solute in solution is greater than the pure solute

Question 5

spontaneous reaction

Answer 5

• change in G is less than 0
• E of cell is greater than 0
• K is greater than 1

Question 6

characteristics of enthalpy

Answer 6

• if change in H is less then 0, then exothermic

- if change in H is greater then 0, then endothermic

Question 7

first law of thermodynamics

Answer 7

energy/mass of the universe is constant

Question 8

second law of thermodynamics

Answer 8

the entropy of the universe is always increasing

Question 9

third law of thermodynamics

Answer 9

entropy of a pure and perfect crystal at absolute zero is zero

Question 10

in line notation which elements go on the left and which on the right

Answer 10

oxidation is on left and reduction is on the right

Question 11

spontaneous reaction

Answer 11

one that occurs without ongoing outside intervention such as work and external force

Question 12

enthalpy

Answer 12

sum of internal energy of a system and product of its pressure and volume

Question 13

entropy

Answer 13

thermodynamic function with the number of energetically equivalent ways to arrange the components of a system to achieve a particular state

Question 14

standard entropy change for a reaction

Answer 14

change in entropy for process in which all reactants and products are in standard states

Question 15

allotropes

Answer 15

an element that can exist in two or more forms

Question 16

reversible reaction

Answer 16

reaction that achieves theoretical limit with respect to free energy

Question 17

irreversible reaction

Answer 17

do not achieve the theoretical limit of available free energy

Question 18

electrical current

Answer 18

flow of electrical current

Question 19

electrochemical cell

Answer 19

device in which the generation of electricity through redox reactions occur
reduced on right and oxidized on left

Question 20

half-cell

Answer 20

one half of an electrochemical cell where either oxidation or reduction occurs

Question 21

electrodes

Answer 21

conductive surfaces through which electrons can enter or leave half-cells

Question 22

cell potential

Answer 22

measure of overall tendency of the redox reaction to occur spontaneously

Question 23

anode

Answer 23

electrode where oxidation occurs

Question 24

cathode

Answer 24

electrode where reduction occurs

Question 25

salt bridge

Answer 25

device used that connects half-cells to give the counterions a pathway to continue motion

Question 26

standard electrode potential

Answer 26

where each half-cell has its own potential

Question 27

standard hydrogen electrode (SHE)

Answer 27

half-cell electrode that is normally chosen to have a potential of zero (platinum)