An element X has a total of 31 nucleons, out of which 16 are neutrons.
Determine the group and period number of element X.

Explanation

To determine the group and period number of element X, follow these steps:

### Step 1: Understand the Given Information
You are given that element X has a total of 31 nucleons and 16 of these are neutrons.

### Step 2: Calculate the Mass Number
The mass number (A) is the total number of nucleons, which is given as:
- Mass Number (A) = 31
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