Complete the following table :

Explanation

(a) First row :
(i) Since the atomic number is given to be 9, therefore, the number of protons is 9 and the number of electrons is also 9
(ii) Mass number is equal to the number of protons plus the number of neutrons, that is, mass number = `9 + 10 =19`
(iii) The atomic species having atomic number 9 is fluorine
(b) Second row :
(i) Since the atomic number is given to be 16, therefore, the number of protons is 16 and the number of electrons is also 16
(ii) Number of neutrons is equal to mass number minus the number of protons, that is, number of neutrons `= 32 - 16 = 16`
(c) Third row :
(i) Since the number of protons is given to be 12, so the atomic number is 12 and the number of electrons is also 12
(ii) Number of neutrons is equal to mass number minus the number of protons, that is, number of neutrons `= 24 - 12 =12`
(iii) The atomic species of atomic number 12 is magnesium
(d) Fourth row :
(i) Since the number of protons is given to be 1, so the atomic number is 1 and the number of electrons is also 1.
(ii) Number of neutrons is equal to mass number minus the number of protons, that is, number of neutrons `= 2-1=1`
(iii) The atomic species of atomic number 1 and mass number 2 is heavy hydrogen or deuterium
(e) Fifth row :
(i) Since th number of protons is 1, so the atomic number is also 1
(ii) The atomic species of atomic number 1 and mass number 1 is ordinary hydrogen or protium
We can now write the completed Table as follows :