Question

The least number of molecules are contained in:

• A. 2 g hydrogen
• B. 8 g oxygen
• C. 4 g nitrogen
• D. 16 g $C{O}_2$

Answer 1

The correct option is C 4 g nitrogen

Number of moles in,
(1) $2$ gm hydrogen = one mole hydrogen gas
(2) $8$ gm of oxygen = $8/32=0.25$ moles of oxygen gas
(3) $4$ gm of nitrogen = $4/28=1/7$ moles of nitrogen gas
(4) $16$ gm of $C{O}_2$ = $16/44=0.36$ moles
So, the lowest no. of moles will have the lowest number of molecules.

Hence, option C is correct.