Give one method of preparation of sodium thiosulfate.

Explanation

To prepare sodium thiosulfate (Na2S2O3), we can use the following method:

### Step-by-Step Preparation of Sodium Thiosulfate

1. **Identify Reactants**: The first step is to identify the reactants needed for the reaction. In this case, we will use sodium sulfide (Na2S) and sodium sulfite (Na2SO3) as our reactants.

2. **Reaction with Iodine**: The next step involves the reaction of the identified reactants with iodine (I2). The balanced chemical equation for the reaction is:
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