State whether each of the following processes is exothermic or endothermic : `KCl (s) + aq to KCl (aq) , DeltaH = + 18.6 kJ `

Explanation

To determine whether the process of dissolving KCl (s) in water to form KCl (aq) is exothermic or endothermic, we can follow these steps:

### Step 1: Identify the Process
The process given is the dissolution of solid potassium chloride (KCl) in water, which can be represented as:
\[ \text{KCl (s)} + \text{H}_2\text{O (l)} \rightarrow \text{KCl (aq)} \]

### Step 2: Analyze the Enthalpy Change
The enthalpy change (ΔH) for this process is given as +18.6 kJ.
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