Write one reaction using alkaline `KmnO_4`.

Explanation

To write a reaction using alkaline KMnO4, we can consider the reaction of an alkene with cold dilute alkaline potassium permanganate. Here is a step-by-step breakdown of the reaction:

### Step 1: Identify the Reactants
We will use ethylene (ethene), which is represented as \( \text{CH}_2= \text{CH}_2 \), as our alkene. The other reactant is cold dilute alkaline potassium permanganate (\( \text{KMnO}_4 \)).

### Step 2: Write the Reaction
The reaction between ethylene and cold dilute alkaline KMnO4 leads to the formation of a diol. The reaction can be written as follows:

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