Question

An atom of an element has three electrons in the third shell which is the outermost shell. Write (a) the electronic configuration (b) the atomic number (c) number of protons (d) valency (e) the name of the element (f) its nature whether metal or non-metal.​

Answer 1

Answer:

a) K = 2 L= 8 M= 3

b) 13 ( 2+8+3)

c) no. of protons = atomic no. = 13

d) valency = 3

e) Aluminum (Al)

f) Its a Metal

Answer 2

Following are the answers to the given questions based on the information provided:-

a) 2,8,3  b)13  c)13  d)3   e)Aluminium  f)Metal

a) 2,8,3

• 4 shells are filled in electronic configuration - K, L, M, N shells are to be filled.
• Maximum electrons that can be filled in respective shells are:
• K - 2, L - 8, M - 8, N - 8, therefore in this case 3 electrons in the outermost shell hence 2,8,3.

b) Atomic number = number of electrons = number of protons present in the nucleus of each atom of the element.

• 2 + 8 + 3 = 13

c) number of protons = 13

d) Valency = It the chemical combining capacity of the element or the number of electrons in the valence shell i.e. the last shell, Hence valence electrons or valency = 3

e)Name of the element is Aluminium as it has an atomic number of 13.

f) Aluminium is a metal. Metals are lustrous, ductile, conductors of electricity that form cations or positively charged ions by losing electrons.