Among alkali metal ions ………..ion has highest polarizing power.

Explanation

To determine which alkali metal ion has the highest polarizing power, we can follow these steps:

### Step 1: Understand Polarizing Power
Polarizing power refers to the ability of a cation (positive ion) to distort the electron cloud of an anion (negative ion). The greater the polarizing power, the more the cation can distort the electron cloud of the anion, leading to stronger ionic character.

### Step 2: Identify Alkali Metal Ions
The alkali metal ions include:
- Lithium ion (Li⁺)
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