An element X belongs to 3rd period and group II of the periodic table . State :
the valency .

Explanation

To determine the valency of the element X that belongs to the 3rd period and group II of the periodic table, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Element**:
- The element X is in the 3rd period and group II of the periodic table.
- Elements in group II are known as alkaline earth metals. The elements in this group include Magnesium (Mg) and Calcium (Ca) in the 3rd period.

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