A uranium nucleus (atomic number `92`, mass number `231`) emits an `alpha`-particle and the resultant nucleus emits a `beta`-particles. What are the atomic and mass numbers of the final nucleus? .

Explanation

To solve the problem step-by-step, we will analyze the decay processes of the uranium nucleus.

### Step 1: Identify the initial properties of the uranium nucleus.
- The atomic number (Z) of uranium is 92.
- The mass number (A) of uranium is 231.

### Step 2: Determine the effect of alpha decay.
An alpha particle consists of 2 protons and 2 neutrons. When the uranium nucleus emits an alpha particle, the following changes occur:
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