exam 2 chapter 18

Question 1

standard molar entropy values

Answer 1

can be measured against the absolute zero of entropy (defined by third law of thermodynamics)

Question 2

standard entropies for elements in their standard state are

Answer 2

always nonzero

Question 3

standard entropy change for a reaction means the change in entropy for the process in which

Answer 3

all products and reactants are in their standard states

Question 4

gas =

Answer 4

pure gas at exactly 1 atm pressure

Question 5

liquid/solid =

Answer 5

pure liquid or solid in its most stable form at 1 atm pressure and temp of interest

Question 6

solution =

Answer 6

substance in a solution with concentration of 1 M

Question 7

the free energy of formation (ΔGf) is the change in free energy when

Answer 7

1 mol of compound in its standard states forms its constituents’ elements in their standard states

Question 8

free energy of formation of pure elements in their standard state

Answer 8

is zero

Question 9

if chemical equation is multiplied by some factor the value of ΔG rxn is

Answer 9

also multiplied by same factor

Question 10

if chemical equation is reversed ΔG rxn

Answer 10

changes signs

Question 11

ΔG is a

Answer 11

state function

Question 12

If a chemical equation can be expressed as a series of reactions, the overall equation

Answer 12

is the sum of the free energies of reactants for each step