| I. 5 moles of \[\text{C}{{\text{O}}_{\text{2}}}\] and 5 moles of \[{{\text{H}}_{\text{2}}}\text{O}\] have the same mass. |
| II. 100 g of \[\text{N}{{\text{H}}_{\text{3}}}\] has more atoms than that present in 100 g of \[{{\text{N}}_{\text{2}}}\]. |
| III. 16 g of solid sulphur contains \[\text{3}\text{.76}\times \text{1}{{\text{0}}^{\text{22}}}\] molecules. |
A) I and II only
B) II and III only
C) III only
D) I only
Correct Answer: B
Solution :
I. 5 moles of \[\text{C}{{\text{O}}_{\text{2}}}\text{=44}\times \text{5=220 g}\] 5 moles of \[{{\text{H}}_{\text{2}}}\text{O}=18\times 5=90\text{ }g\] Hence, 5 moles of \[\text{C}{{\text{O}}_{\text{2}}}\] and 5 moles of \[{{\text{H}}_{2}}\text{O}\]do not have the same mass. II. 100 g of \[\text{N}{{\text{H}}_{\text{3}}}\]: 17 g of \[\text{N}{{\text{H}}_{3}}\equiv 6.023\times {{10}^{23}}\times 3\] atoms \[100\text{ g of N}{{\text{H}}_{3}}\equiv \frac{6.023\times {{10}^{23}}\times 3}{17}\times 100\] \[=106.29\times {{10}^{23}}\] atoms \[100\text{ g of }{{\text{N}}_{2}}=\frac{2\times 6.023\times {{10}^{23}}}{28}\times 100\] \[=\text{ }43.02\times {{10}^{23}}\] atoms Hence, 100 g of \[\text{N}{{\text{H}}_{\text{3}}}\] has more atoms than 100 g of \[{{\text{N}}_{\text{2}}}\]. III. \[8\times 32\text{ }g\] of sulphur \[\equiv \frac{6.023\times {{10}^{23}}}{8\times 32}\times 16\] \[=0.376\times {{10}^{23}}\] molecules \[=3.76\times {{10}^{22}}\,\,\text{molecules}\]
You need to login to perform this action.
You will be redirected in
3 sec
