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What drives spontaneous reactions?

Select one:
a. decreasing enthalpy and decreasing entropy
b. decreasing enthalpy and increasing entropy
c. increasing enthalpy and decreasing entropy
d. increasing enthalpy and increasing entropy

User Hwatkins
by
5.3k points

2 Answers

3 votes

Answer:

b. decreasing enthalpy and increasing entropy

Step-by-step explanation:

∆H stands for enthalpy change and ∆S stands for entropy change

Spontaneity depends on the enthalpy and entropy changes of the reaction

∆G = ∆H - T∆S

When ∆H is negative and ∆S is positive

∆G will be negative

For a spontaneous reaction ∆G is negative

If ∆G = 0 then the reaction will be at equilibrium

If ∆G is positive the reaction is non spontaneous.

Decreasing enthalpy (negative) and increasing entropy (positive) will give a negative number for
\Delta G

User Hannes M
by
5.7k points
1 vote

Answer:

option B

Step-by-step explanation:

A spontaneous reaction drive favorable when enthalpy is decreasing and the entropy is increasing on the system. If that happens the reaction occurs spontaneously

User Kuldeep Yadav
by
5.1k points