Which one is least ionic in the following compounds

Options

A. `AgCl `
B. `KCl `
C. `BaCl_2`
D. `CaCl_2`

Explanation

To determine which compound is least ionic among the given options, we need to analyze the ionic character of each compound based on the size of the cations involved. Here’s a step-by-step solution:

### Step 1: Understand Ionic Character
Ionic character in a compound is influenced by the size of the cation and the anion. Generally, larger cations lead to higher ionic character because they can polarize the electron cloud of the anion more effectively.

### Step 2: Identify the Cations
In the compounds provided, we need to identify the cations present:
- Ca²⁺ (Calcium)
- Ba²⁺ (Barium)
- K⁺ (Potassium)
- Ag⁺ (Silver)

### Step 3: Compare the Sizes of Cations
The ionic character increases with the size of the cation. The order of size from largest to smallest for the cations is:
1. Ba²⁺ (largest)
2. K⁺
3. Ca²⁺
4. Ag⁺ (smallest)

### Step 4: Determine Ionic Character Order
Based on the size of the cations, we can determine the order of ionic character for the compounds:
- BaCl₂ (most ionic due to Ba²⁺ being the largest cation)
- KCl
- CaCl₂
- AgCl (least ionic due to Ag⁺ being the smallest cation)

### Step 5: Conclusion
From the analysis, we conclude that the compound with the least ionic character is **AgCl**.

### Final Answer
The least ionic compound among the options is **AgCl**.

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