Question

The largest number of molecules among the following is in

• A. $28\text{g of}CO$
• B. $46\text{g of}{C}_2{H}_{5}OH$
• C. $36\text{g of}{H}_{2}O$
• D. $54\text{g of}{N}_2{O}_5$

Answer 1

The correct option is C $36\text{g of}{H}_{2}O$

No. of mole of $C{O}_2$ = weight/m.w = 28/28 = 1 mole
No. of mole of $C_2{H}_{5}OH$ = weight/m.w = 46/46 = 1 mole
No. of mole of $H_{2}O$ = weight/m.w = 36/18 = 2 mole
No. of mole of $N_2{O}_5$ = weight/m.w = 54/108 = 0.5 mole
So, $36g$ of $H_{2}O$ will contain largest no. of molecules among all.