Which one of the following will have the largest number of atoms?
(i) 1 g Au (s)
(ii) 1 g Na (s)
(iii) 1 g Li (s)
(iv) 1 g of Cl2(g)

Explanation

No. of atoms can be calculated as:
(i) 1g Au `1/197 xx 6.022 xx 10^(23) =(6.022)/197 xx 10^(23)`
(i) 1g Na `=(6.022)/23 xx 10^(23)`
(iii) 1 g Li `=(6.022 xx 10^(23))/7`
(iv) 1g `Cl_(2) =(2 xx 6.022 xx 10^(23))/71 = (6.022 xx 10^(23))/35.5`
It is clear that 1 g Li contains largest number of atoms.