An element 'X' belongs to the third period of the p-block elements. It has four electrons in the outermost shell. The name of the element is

Options

A. Aluminium
B. Silicon
C. Germanium
D. Sulphur

Answer

To determine the name of the element 'X' that belongs to the third period of the p-block elements and has four electrons in its outermost shell, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Period**:
- The question states that the element 'X' is in the third period of the periodic table. The third period includes elements from sodium (Na) to argon (Ar).

2. **Identify the Block**:
- The element is specified to be in the p-block. In the periodic table, the p-block elements start from group 13 (III A) to group 18 (VIII A).

3. **Determine the Number of Electrons in the Outermost Shell**:
- The element has four electrons in its outermost shell. In the context of the periodic table, this means we need to consider the distribution of electrons in the outermost energy level (n=3 for the third period).

4. **Electron Configuration**:
- The general electron configuration for the third period elements is:
- For s-block: 3s²
- For p-block: 3p¹, 3p², 3p³, etc.
- Since the element has four electrons in total in the outermost shell, we can deduce its configuration:
- 3s² (2 electrons) + 3p² (2 electrons) = 4 electrons.

5. **Identify the Element**:
- The element with the electron configuration of 3s² 3p² corresponds to silicon (Si), which has an atomic number of 14.

6. **Final Answer**:
- Therefore, the name of the element 'X' is **Silicon**.

### Summary:
The element 'X' is Silicon (Si), which is in the third period of the p-block and has four electrons in its outermost shell.