In a regular octahedral molecule `MX_(6)` the number of `X - M - X` bonds at `180^(@)` is

Options

A. 3
B. 2
C. 6
D. 4

Explanation

To solve the problem of determining the number of `X - M - X` bonds at `180°` in a regular octahedral molecule `MX₆`, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Octahedral Molecule**:
- An octahedral molecule has a central atom (M) surrounded by six atoms (X) at the corners of an octahedron. The geometry is symmetrical.

2. **Visualize the Octahedral Geometry**:
- In an octahedral arrangement, the six `X` atoms are positioned such that four of them lie in the same plane (forming a square), while the other two are positioned above and below this plane.

3. **Identify the Bond Angles**:
- In this structure, the angles between the bonds are crucial. The bonds in the plane are at `90°` to each other, while the bonds that extend above and below the plane are `180°` apart from each other.

4. **Count the `180°` Bonds**:
- To find the number of `X - M - X` bonds that are at `180°`, we can analyze the pairs:
- The two `X` atoms in the same plane can be paired with the two `X` atoms in the opposite plane (above and below), which gives us one pair.
- Additionally, the two `X` atoms in the plane can be paired with each other, which gives us another pair.
- Finally, the bond extending above the plane and the bond extending below the plane also forms a `180°` angle.

5. **Total Count**:
- Therefore, we have three distinct pairs of `X - M - X` bonds that are at `180°`.

### Final Answer:
The number of `X - M - X` bonds at `180°` in a regular octahedral molecule `MX₆` is **3**.

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