For a single substance at atmospheric pressure, classify the following as describing a spontaneous process, a nonspontaneous process, or an equilibrium system. A) Solid melting below its melting point
B) Gas condensing below its condensation point
C) Liquid vaporizing above its boiling point
D) Liquid freezing below its freezing point
E) Liquid freezing above its freezing point
F) Solid melting above its melting point
G) Liquid and gas together at boiling point with no net condensation or vaporization
H) Gas condensing above its condensation point
I) Solid and liquid together at the melting point with no net freezing or melting

A) Solid melting below its melting point - nonspontaneous process

B) Gas condensing below its condensation point - spontaneous process

C) Liquid vaporizing above its boiling point - spontaneous process

D) Liquid freezing below its freezing point - spontaneous process

E) Liquid freezing above its freezing point - nonspontaneous process

F) Solid melting above its melting point - spontaneous process

G) Liquid and gas together at boiling point with no net condensation or vaporization - Equilibrium system

H) Gas condensing above its condensation point - nonspontaneous process

I) Solid and liquid together at the melting point with no net freezing or melting -  Equilibrium system

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Spontaneous process- This is the process that occurs on its own without the application of any external energy or other factor. They include

B) Gas condensing below its condensation point

C) Liquid vaporizing above its boiling point

D) Liquid freezing below its freezing point

F) Solid melting above its melting point

Non spontaneous - This is the process that doesn’t occurs on its own and requires the application of any external energy or factor. They include

A) Solid melting below its melting point

E) Liquid freezing above its freezing point

H) Gas condensing above its condensation point

Equilibrium system

G) Liquid and gas together at boiling point with no net condensation or vaporization

I) Solid and liquid together at the melting point with no net freezing or melting

the answer is na (sodium)