Answer
(i) $180 \space g$
(ii) $1.77 \space N$
Work Step by Step
1. Calculate the molar mass of water $\big(H_2O\big)$:
$H: 1.0 \times 2 = 2.0$
$O : 16.0 \times 1 = 16.0$
Molar mass of water = $2.0 + 16.0 = 18.0 \space g/mol$
2. Find the mass of 10.0 mol $H_2O$:
$$10.0 \space mol \times \frac{18.0 \space g}{1 \space mol} = 180. \space g$$
3. Calculate the weight on the surface of the Earth:
$Weight = mg = (180. \space g)(9.81 \space m/s^2) = 1770 \space g \space m/s^2$
Normally, the weight is expressed in $N$, which is $kg \space m/s^2$. Thus, we should convert the mass into $kg$:
$$Weight = 1770 \space g \space m/s^2 \times \frac{1 \space kg}{1000 \space g} = 1.77 \space N$$
