The experimentally determined `N-F` bond length in `NF_(3)` is _____than the sum of the single covalent bond radii of `N` and `F` .

Explanation

To determine the relationship between the experimentally determined N-F bond length in NF₃ and the sum of the single covalent bond radii of nitrogen (N) and fluorine (F), we can follow these steps:

### Step 1: Understand the Concept of Bond Length and Covalent Radii
- The bond length is the distance between the nuclei of two bonded atoms.
- The covalent radius is a measure of the size of an atom when it is covalently bonded to another atom.

### Step 2: Identify the Atoms Involved
- In this case, we are looking at nitrogen (N) and fluorine (F), both of which are in the second period of the periodic table.

### Step 3: Consider the Sizes of N and F
- Both nitrogen and fluorine are relatively small atoms. Their small sizes lead to a dense electron cloud around them.

### Step 4: Analyze the Electron Cloud Density
- The dense electron cloud between the two atoms can cause repulsion due to the increased electron-electron interactions.

### Step 5: Relate Bond Length to Covalent Radii
- Due to the repulsion caused by the dense electron cloud, the bond length (the distance between the nitrogen and fluorine nuclei) is expected to be greater than the simple sum of their covalent radii.

### Conclusion
- Therefore, the experimentally determined N-F bond length in NF₃ is **greater** than the sum of the single covalent bond radii of nitrogen and fluorine.

### Final Answer
The experimentally determined N-F bond length in NF₃ is **greater** than the sum of the single covalent bond radii of N and F.

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