Arrange the following in the order of their increasing size : `Cl^(-) , S^(2-) , Ca^(2+) , Ar`

Explanation

To arrange the ions Cl^(-), S^(2-), Ca^(2+), and Ar in order of their increasing size, we will follow these steps:

### Step 1: Identify the number of electrons
- Cl^(-) has 17 protons and gains 1 electron, giving it a total of 18 electrons.
- S^(2-) has 16 protons and gains 2 electrons, giving it a total of 18 electrons.
- Ca^(2+) has 20 protons and loses 2 electrons, giving it a total of 18 electrons.
- Ar has 18 protons and has 18 electrons.

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