Spontaneous reaction, Gibbs Free energy change Exam Prep Quiz

A reaction is spontaneous when:

It occurs without continuous external energy input

The symbol for entropy is:

S

Entropy is best described as:

Degree of disorder

Enthalpy refers to:

Heat content of a system

A reaction with negative ΔG is:

Spontaneous

A reaction with positive ΔG is:

Nonspontaneous

Exergonic reactions:

Release free energy

Endergonic reactions:

Require energy input

A reaction is exothermic when:

ΔH is negative

A reaction is endothermic when:

ΔH is positive

The Gibbs free energy equation is:

ΔG = ΔH – TΔS

Increasing entropy generally makes reactions:

More spontaneous

Temperature affects spontaneity because it:

Multiplies the entropy term (TΔS)

A reaction with negative ΔH and positive ΔS is:

Always spontaneous

A reaction with positive ΔH and positive ΔS is spontaneous:

At high temperatures

A reaction with negative ΔH and negative ΔS is spontaneous:

At low temperatures

A reaction with positive ΔH and negative ΔS is:

Never spontaneous

Entropy increases when:

Solid becomes gas

A spontaneous reaction:

May occur slowly

Free energy is:

Energy available to do work

When ΔG = 0, the system is:

At equilibrium

Entropy of a system increases when:

Molecules become more disordered

A reaction that releases heat is:

Exothermic

A reaction that absorbs heat is:

Endothermic

Entropy is measured in:

J/mol·K

Enthalpy is measured in:

kJ/mol

A reaction becomes more spontaneous as:

ΔG decreases

A reaction with ΔG < 0 is:

Exergonic

A reaction with ΔG > 0 is

Endergonic

Entropy tends to increase when:

Molecules disperse