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Explain what the ΔH and ΔG values mean. What do the negative signs mean in each case?

A) ΔH represents the change in entropy, and a negative sign means an endothermic reaction.
ΔG represents the change in free energy, and a negative sign indicates a reaction that absorbs energy.
B) ΔH represents the change in enthalpy, and a negative sign means an exothermic reaction.
ΔG represents the change in Gibbs free energy, and a negative sign indicates a spontaneous reaction.
C) ΔH represents the change in heat, and a negative sign means an endothermic reaction.
ΔG represents the change in entropy, and a negative sign indicates a reaction that releases energy.
D) ΔH represents the change in entropy, and a negative sign means an exothermic reaction.
ΔG represents the change in enthalpy, and a negative sign indicates a non-spontaneous reaction.

User Tie
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Final answer:

Option B: ΔH represents enthalpy change; negative indicates exothermic reactions. ΔG represents Gibbs free energy change; negative means the reaction is spontaneous.

Step-by-step explanation:

ΔH represents the change in enthalpy, and when it is negative, it indicates an exothermic reaction, which means heat is released by the system. Conversely, if ΔH is positive, the reaction is endothermic, meaning heat is absorbed by the system. ΔG stands for the change in Gibbs free energy, and a negative ΔG signifies a spontaneous reaction. A spontaneous reaction may not occur immediately, but it is favorably inclined to proceed under certain conditions without the need for additional energy.

The ΔH value represents the change in enthalpy of a reaction. Enthalpy refers to the total energy of a system. A negative sign in ΔH indicates an exothermic reaction, where heat is released by the system into the surroundings. On the other hand, a positive sign in ΔH indicates an endothermic reaction, where heat is absorbed by the system from the surroundings.

The ΔG value represents the change in Gibbs free energy of a reaction. Gibbs free energy is a measure of the energy available to do useful work in a system. A negative sign in ΔG indicates a spontaneous reaction, where the reaction proceeds without the need for external energy. Conversely, a positive sign in ΔG indicates a non-spontaneous reaction, where the reaction requires external energy input to proceed.

User Roberto Lo Giacco
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