certain particle x has 17 protons 17 electrons and 18 neutrons
(i) What is the mass number of X?
(ii) What is atomic number of X?
(iii) What is valency of X?
(iv) identify the elemnet.

Explanation

(i) Mass no of X= No of p + No of n = Valency of x
(iii) Electronic configuration of X = (i) Mass no of X=No of p,+ No of n = p + NO of n = =
(ii) Atomic no of X=No of
(iii) Electronic configuration of X = 2,8,7
valency of X=(8-7)=1
(iv) Name of element X= Chlorine (CI) ,