Question

which is not true of the sc³⁺ ion?

a) it was formed by the loss of 4s and 3d electrons.
b) it has the same electron configuration as ar.
c) it is a scandium ion with three positive charges.
d) it is considered to be a different element than a neutral sc atom.

Explanation:

Step1: Analyze option A

The electron configuration of Sc is \([Ar]3d^{1}4s^{2}\). When forming \(Sc^{3 +}\), it loses 3 electrons. First, it loses 2 electrons from the 4s orbital and then 1 electron from the 3d orbital. So, it is not formed by the loss of 4s and 3d electrons simultaneously in the way described in option A.

Step2: Analyze option B

The electron configuration of \(Sc^{3+}\) is \([Ar]\), which is the same as that of Ar.

Step3: Analyze option C

By the definition of \(Sc^{3+}\), it is a scandium ion with three positive charges.

Step4: Analyze option D

An ion (\(Sc^{3+}\)) and a neutral atom (Sc) of the same element have different charges and electron - related properties, but they are of the same element. However, option D is wrong in the sense that it is not a different element. But option A is more clearly wrong.

So, the answer is A.

Answer:

A. It was formed by the loss of 4s and 3d electrons.