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Enthalpy and entropy

Question 7

An instant cold pack is activated by breaking an internal barrier, allowing solid ammonium nitrate ( $NH4NO3\text{NH}_4\text{NO}_3$ ) to dissolve in water. This process results in a rapid decrease in the temperature of the surroundings.

What are the signs of the enthalpy change ( $ΔH\Delta H$ ) and the entropy change ( $ΔS\Delta S$ ) for this dissolution process?

$ΔH\Delta H$ is negative and $ΔS\Delta S$ is positive

$ΔH\Delta H$ is positive and $ΔS\Delta S$ is negative

$ΔH\Delta H$ is positive and $ΔS\Delta S$ is positive

$ΔH\Delta H$ is negative and $ΔS\Delta S$ is negative

Markscheme

Enthalpy and entropy Questions

A Level
Chemistry
Enthalpy and entropy

24 exam-style questions on OCR A A Level Chemistry Enthalpy and entropy. Each one has a worked solution and a mark scheme showing where the marks go.

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