A sigma bonded molecule `MX_(3)` is T-shaped The number of non-bonding pairs of electrons is .

Options

A. `2`
B. `1`
C. `0`
D. Can be predicted only if atomic number of `M` is known

Explanation

To determine the number of non-bonding pairs of electrons in the T-shaped molecule \( MX_3 \), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Molecular Formula**: The molecule is given as \( MX_3 \), indicating that there is one central atom (M) bonded to three surrounding atoms (X).

2. **Determine the Hybridization**: For a molecule with the formula \( MX_3 \) and a T-shaped geometry, we need to consider the hybridization. The T-shaped structure typically arises from \( sp^3d \) hybridization, which is associated with a trigonal bipyramidal electron geometry.

3. **Count the Bonding Pairs**: In \( MX_3 \), there are three bonding pairs of electrons (one for each \( MX \) bond).

4. **Determine the Total Electron Pairs**: In \( sp^3d \) hybridization, there are a total of five electron pairs (3 bonding pairs + 2 non-bonding pairs).

5. **Calculate Non-Bonding Pairs**: Since we have 3 bonding pairs and a total of 5 electron pairs, the number of non-bonding pairs (lone pairs) can be calculated as:
\[ \text{Non-bonding pairs} = \text{Total electron pairs} - \text{Bonding pairs} = 5 - 3 = 2 \]

6. **Conclusion**: Therefore, the number of non-bonding pairs of electrons in the T-shaped molecule \( MX_3 \) is 2.

### Final Answer:
The number of non-bonding pairs of electrons is **2**.

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