Give the formulae of the species that will be isoelectron c with the following atoms or ions :
Rb

Explanation

To find the species that are isoelectronic with rubidium ion (Rb⁺), we need to follow these steps:

### Step 1: Determine the electron configuration of rubidium (Rb)
- Rubidium has an atomic number of 37, which means it has 37 electrons in its neutral state. The electron configuration of rubidium is:
\[ \text{Rb: } [Kr] 5s^1 \]

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