Question

The number of moles of water in $1.8$ litres of pure water is (density of water $=$ 1 g/ml) ?

• A. $18$
• B. $100$
• C. $36$
• D. $55.4$

Answer 1

Answer: (B)

$100$

Density of water $=1gm/ml$

Since 1 ml of water weights $=1gm$

$\therefore$ 1800 ml water weighs $=1800gm$

Now, 18 gm of water contains $=1mole$

$\therefore$ 1800 gm of water contains $=\frac{1\times 1800}{18}=100moles$