Which of the following pairs have the same number of atoms ?

Options

A. 16 g of `O_(2)` (g) and 4 g of `H_(2)(g)`
B. 16 g of `O_(2)` and 44 g of `CO_(2)`
C. 28 g of `N_(2)` and32 g of `O_(2)`
D. 12 g of C(s) and 23 g of Na(s)

Answer

C, D

Explanation

`16g O_(2)=16//32" mole = 0.5 mole "=0.5xxN_(A)" molecules "=2xx0.5xxN_(A)" atoms"=N_(A)" atoms"`
`4g H_(2)=4//2" mole = 2 mole "=2xxN_(A) " molecules"=2xx2xxN_(A)" atoms"=4N_(A)" atoms"`
`"44 g of CO"_(2)=44//44" mole = 1 mole "=N_(A)" molecules"=3xxN_(A)" atoms "=3N_(A)" atoms"`
`28g N_(2)=28/28" mole = 1 mole "=N_(A)" molecules "=2xxN_(A)" atoms"=2N_(A)" atoms"`
`32gO_(2)=2N_(A)` atoms (as solved above)
`12gC=12//12" mole = 1 mole "=N_(A)" atoms"`
`23g Na=23//23 " mole = 1 mole "=N_(A)" atoms"`
Thus, (c) and (d) are correct.