Calculate :
the volume measured at S.T .P. of carbon dioxide released when 8.40 g of sodium hydrogen carbonate is decomposed according to the equation :
`2NaHCO_(3)toNa_(2)CO_(3)+H_(2)O+CO_(2)`
(Na = 23, H = 1, C = 12, O = 16)

Explanation

To solve the problem of calculating the volume of carbon dioxide (CO₂) released when 8.40 g of sodium hydrogen carbonate (NaHCO₃) decomposes, we will follow these steps:

### Step 1: Write the balanced chemical equation
The decomposition of sodium hydrogen carbonate can be represented by the following balanced equation:
\[ 2 \text{NaHCO}_3 \rightarrow \text{Na}_2\text{CO}_3 + \text{H}_2\text{O} + \text{CO}_2 \]

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