Calculate the number of protons , electrons and neutrons in the following.
(a) Chloride ion `(Cl^(-))` with `Z = 17,A =35`
(b) Aluminium ions`(Al^(3+)) ` with `Z = 13 , A=27`

Explanation

(a)`Cl^(-) ` with `Z = 17 , A= 35`
Number of protons`= 17`
Number of electrons `=17 +1` ( As one negative charge which means gains of electron) `=18`
Number of neutrons `= A-Z = 35 - 17 = 18`
( b) `Al^(3+)` with `Z= 13 `
`A=27`
Number of protons `= 13`
Number of electrons `=13-3 = 10 ` ( As it has three positive charge obtained by the loss of three electrons)
number of neutrons `= A-Z= 27-13=14`