The bond length in LiF will be

Options

A. Less than that of NaF
B. Equal to that of KF
C. More than that of KF
D. Equal to that of NaF

Answer

To determine the bond length in LiF and how it compares to other similar compounds, we can follow these steps:

### Step 1: Understand the Concept of Bond Length
Bond length is the distance between the nuclei of two bonded atoms. It is influenced by the size of the atoms involved and the type of bond (ionic or covalent).

### Step 2: Compare the Cations
In LiF, we have lithium (Li) and fluorine (F). To compare the bond lengths of LiF with NaF and KF, we need to consider the sizes of the cations:
- Li⁺ is smaller than Na⁺ and K⁺.
- As we move down the group in the periodic table, the size of the cation increases.

### Step 3: Analyze the Bond Lengths
Since Li⁺ is smaller than Na⁺ and K⁺, the bond length in LiF will be less than that in NaF and KF. This is because a smaller cation will lead to a shorter distance between the nuclei of Li and F.

### Step 4: Consider the Covalent Character
LiF has a significant covalent character due to the small size of Li⁺, which allows for a closer approach of the electron clouds of Li and F. Generally, the more covalent a bond is, the shorter the bond length tends to be.

### Step 5: Conclusion
Therefore, we can conclude that the bond length in LiF is less than that in NaF and KF, and it can also be stated that the bond length in LiF is less than or equal to that in NF (if we consider the bond character).

### Final Answer
The bond length in LiF will be less than that of NaF and KF.

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