Destroyer GC Question

[john216]

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The question is
An unknown compound dissolves in H2O spontaneously. If the temperature of the water decreases, which is true?

The answer says Delta H is positive because its endothermic.

I don't understand why its endothermic. If the temperature decreased, that means the heat is released from the system to surrounding which makes it exothermic.

Can anyone help me?

 

[LazyP]

If the temperature of the water increased, then it would be exothermic because the compound which dissolved released heat into the surrounding (water). The temperature decreased, so heat was taken from the surroundings, water, to dissolve the compound.

 

[Intent]

Solid --> Liquid --> Gas +ΔH, +ΔS

Gas --> Liquid --> Solid -ΔH, -ΔS

 

[hope_to_match]

If the temperature of the water increased, then it would be exothermic because the compound which dissolved released heat into the surrounding (water). The temperature decreased, so heat was taken from the surroundings, water, to dissolve the compound.

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