Question

An element has an electronic configuration (2,8,8,1), then the element will be:
A. non-metal
B. metal
C. metalloid
D. noble gas

Answer 1

Hint: As we know that we can get the atomic number of elements from taking the sum of electronic configuration. And can identify the element. By observing where the element is placed in the periodic table we can classify the elements into non-metals, metals, and metalloids.

Complete Solution :
- As we know that the element that has an electronic configuration (2,8,8,1), hence there are two electrons in K shell, 8 electrons in L shell, 8 electrons in M shell and 1 electron in N shell. Thus, the total number of electrons is 19. We can see that the given element is potassium.
- Let’s distinguish between metals, nonmetals and metalloids. It is found that non-metals are poor conductors, brittle and non-lustrous. Metals are lustrous, having good conductivity, malleability and ductility. And metalloids are found to have properties intermediate between metals and nonmetals.
- The element potassium can lose one electron and can become a positive ion, so it is a metal. They are better conductors of electricity than that of nonmetals and metalloids.
- Hence, we can conclude that the correct option is (b), that is an element that has an electronic configuration (2,8,8,1), then the element will be metal.
So, the correct answer is “Option B”.

Note: - We can also find the answer by another way also. As we know that metals have low electro- negativities and nonmetals have high electro-negativities. And the element that has electronic configuration of 2,8,8,1 has low electronegativity.