In 96.0 gm of sulphur calculate (i) the number of gram atoms of the element (ii) the number of gram , molecules, if a molecule of sulphur has the formula,Sg, (iii) the number of atoms of sulphur, and (iv) the „ number of molecules.

(At wt S = 32, Avogadro’s number, N = 6-02 X ${{10}^{23}}$ molecules per mole),

(i) Atomic weight of sulphur = 32 1 gm atom of sulphur = 32 gm

No. of gram atoms in 96 gm of sulphur = 96 /32= 3.

(ii) Molecular weight of ${{S}_{8}}$ = 32 x 8 = 256

.’. No. of gram atoms in 96 gm of sulphur = 96/256 = 0.375.

(iii) 32 gm (1 gm atom) of sulphur contain 6.02 x ${{10}^{23}}$ atoms.

96 gm of sulphur contains 6.02/32 x 96 x ${{10}^{23}}$ = 1.806 x ${{10}^{24}}$ atoms

(iv) 256 gm (1 gm molecule) of sulphur contain 6.02 x ${{10}^{23}}$ molecules

96 gm of sulphur contains 6.02/256 x 96 x ${{10}^{23}}$ =2.257 x ${{10}^{23}}$ molecules.