CH3.7 Entropy and feasibility of reactions

Question 1

Entropy

Answer 1

the degree of freedom of a system. Particles that can move freely in any direction have a much higher entopy than particles that are constrained.

Question 2

units of entropy and sybol representation

units of standard entropy

Answer 2

S and units are JK-1

standard entropy units are JK-1mol-1

Question 3

entropy depending on state

Answer 3

S(solid)

Question 4

entropy equation

Answer 4

chang in S =S(all products) - S (all reactants)

Question 5

secound law of thermodynamics

Answer 5

Entropy will always tend to increase in any isolated system that is not in equilibrium

Question 6

Gibbs free energy equation

Answer 6

(chagne in)G = (change in)H -T(change in)S

Question 7

unit of Gibbs

Answer 7

KJmol-1

or Jmol-1

Question 8

unit of enthalpy

Answer 8

KJmol-1 or Jmol-1

Question 9

when will a reaction occur spontaneously

Answer 9

When the free energy (G) is negative

Question 10

How to work out the temperature at which the reaction is spontaneous

Answer 10

when chagne in G is 0

therefore; H=TS