Question
If an element M has atomic weight 24 and atomic number 12, how many neutrons does its atom contain? How many electrons will be present in K, L and M energy shells of its atom?
Solution
Number of electron = number of protons =12
No. of neutrons = Atomic mass - No. of protons = 24 - 12 =12
Thus,
total number of neutrons =12
So,
Electronic configuration is
K - cell 2 electrons
L - cell 8 electrons
M - cell 2 electrons.
