What amount of heat is liberated during the formation of one gram of `He^(4)` from deuterium `H^(2)`? What mess of coal with calorific value of `30kJ//g` is thermally equivalent to the magnitude obrained?

Explanation

To solve the problem of how much heat is liberated during the formation of one gram of Helium-4 from deuterium (H-2), and to find out the equivalent mass of coal needed to produce that amount of heat, we can follow these steps:

### Step 1: Determine the energy released during the formation of Helium-4
The formation of Helium-4 from two deuterium nuclei can be represented as:
\[ 2 \, ^2H \rightarrow \, ^4He + \text{energy} \]

From nuclear reactions, we know that the energy released (Q) can be calculated using the mass defect and Einstein's equation \(E=mc^2\).

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