Which of the following correctly represents $360 \mathrm{~g}$ of water?
(i) 2 moles of $\mathrm{H}_{2} \mathrm{O}$
(ii) 20 moles of water
(iii) $6.022 \times 10^{23}$ molecules of water
(iv) $1.2044 \times 10^{25}$ molecules of water
(a) (i)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) (ii) and (iv).
Mass of water
(d)
(ii) $\frac{\text { Mass of water }}{\text { Molar mass of water }}$
$=\frac{(360 \mathrm{~g})}{\left(18 \mathrm{~g} \mathrm{~mol}^{-1}\right)}=20 \mathrm{~mol}$
(iv) $18 \mathrm{~g}$ of water represent molecules
$=6.022 \times 10^{23}$
$360 \mathrm{~g}$ of water represent molecules
$=\frac{\left(6 \cdot 022 \times 10^{23}\right)}{(18 \mathrm{~g})} \times(360 \mathrm{~g})$
$=6.022 \times 10^{23} \times 20=1.2044 \times 10^{25}$
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.