If the radius of `K^(+)` and `F^(-)` are 133pm and 136pm respectively, the distance between `K^(+)` and `F^(-)` in KF is

Options

A. 269pm
B. 134.5pm
C. 136pm
D. 3pm

Explanation

To find the distance between \( K^+ \) and \( F^- \) in the compound KF, we can follow these steps:

### Step 1: Identify the radii of the ions
- The radius of \( K^+ \) is given as 133 pm (picometers).
- The radius of \( F^- \) is given as 136 pm.

### Step 2: Understand the distance between the ions
- When \( K^+ \) and \( F^- \) come together to form the ionic compound KF, the distance between the centers of the two ions can be calculated by adding their radii together.

### Step 3: Calculate the distance
- The distance \( D \) between \( K^+ \) and \( F^- \) can be calculated as:
\[ D = \text{radius of } K^+ + \text{radius of } F^- \]
Substituting the values:
\[ D = 133 \, \text{pm} + 136 \, \text{pm} = 269 \, \text{pm} \]

### Step 4: Conclusion
- Therefore, the distance between \( K^+ \) and \( F^- \) in KF is **269 pm**.

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