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.


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Answer 1

Answer:

atom of an elemets has three elctons in the third shell which is the outermost sell .Write <br> (a) the electronic configureation , (b) the atomic number <br> (c ) Eclectronic configuration : 2,8,3 , (d) Valency <br> (e ) the name o f the element , (f) its nature whether metal or non metal

Answer 2

An atom of an element has three electrons in the third shell thus it has 2 electrons in the K shell, 8 in the L shell and 3 in the M shell.

• Thus, the electronic configuration of the element is as follows-
• ${1s}^{2} {2s}^{2} {2p}^{6} {3s}^{2} {3p}^{1}$
• The atomic number of the element is 2+8+3=13.
• The number of protons of the element is equal to the atomic number. Thus, the number of the proton is 13.
• The valency of the element is 3.
• The name of the element is Al or Aluminium.
• It is metal.