The electronic configuration of a transition elements in `+3` oxidatin stateis`[Ar]3d^(7)`. Find out atomic number.

Explanation

To find the atomic number of the transition element with the electronic configuration of `[Ar] 3d^7` in the +3 oxidation state, we can follow these steps:

### Step 1: Understand the Electronic Configuration
The given electronic configuration is `[Ar] 3d^7`. Here, `[Ar]` represents the electron configuration of Argon, which has an atomic number of 18. The `3d^7` indicates that there are 7 electrons in the 3d subshell.

### Step 2: Determine the Total Number of Electrons
In the +3 oxidation state, the element has lost 3 electrons. Therefore, to find the total number of electrons in the neutral atom, we need to add the 3 electrons back to the configuration.

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