Question

Which among the following is transition metal?
A) Sodium
B) Potassium
C) Magnesium
D) Copper

Answer 1

We need to know that the transition metal comes under d block elements in a periodic table. There are inner transition elements also which belong to f block elements. Transition metals are responsible for the color of many complexes due to the presence of unpaired electrons in them.

Complete answer:
We will look at all the options given one by one to answer this question:
Option A) this option is incorrect as sodium is a metal having atomic symbol $Na$, it belongs to the group $1$ that is alkali metals. It has one electron more to attain a stable noble gas configuration having atomic number $11$.
Option B) This option is incorrect as potassium is a metal that comes just after sodium having atomic number $19$, it belongs to alkali metals having atomic symbol $K$.
Option C) this option is incorrect as magnesium is also a metal which belongs to group $2$ i.e. alkaline earth metals. It has an atomic symbol $Mg$ and has two electrons to attain noble gas configuration.
Option D) this option is correct as Copper belongs to transition metal i.e. d block element. It has an atomic number $29$ having electronic configuration represented below:
$\left[ {Ar} \right]3{d^{10}}4{s^1}$
It has one electron less in attaining a stable electronic configuration.

So, the correct answer is “Option D”.

Note:
We need to know that copper is used in making wires and coins. The primary applications of copper are in electrical wiring, roofing, plumbing, and industrial machinery. It is used for a whole range of goods, from cans, cooking foil and saucepans through to electricity cables, planes, and space vehicles.