Arrange the halide ions in order of increasing basicity and nucleophilicity.

Explanation

To arrange the halide ions (fluoride, chloride, bromide, and iodide) in order of increasing basicity and nucleophilicity, we need to consider the properties of these ions.

### Step-by-Step Solution:

1. **Understanding Nucleophilicity**:
- Nucleophilicity refers to the ability of an ion to donate an electron pair to an electrophile. The more electron-rich the ion, the better nucleophile it is.
- In the case of halide ions, as we move down the group from fluorine to iodine, the size of the ions increases. Larger ions have their negative charge spread over a larger volume, making them less effective at donating electrons.

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