The `._(88)^(226)Ra` nucleus undergoes `alpha`-decay to `._(86)^(222)Rn`. Calculate the amount of energy liberated in this decay. Take the mass of `._(88)^(226)Ra` to be `226.025 402 u`, that of `._(88)^(226)Rn` to be `222.017 571 u`, and that of `._(2)^(4)He` to be `4.002 602 u`.

Explanation

To calculate the amount of energy liberated during the alpha decay of the radium nucleus, we can follow these steps:

### Step 1: Write the decay reaction
The alpha decay of radium-226 can be represented as:
\[ _{88}^{226}\text{Ra} \rightarrow _{86}^{222}\text{Rn} + _{2}^{4}\text{He} \]

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