Ordinary water contains one part of heavy water per 6000 parts by weight.The n

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Question -

Ordinary water contains one part of heavy water per 6000 parts by weight.The number of heavy water molecules present in a drop of water of volume 0.01 ml is (Density of water is 1 g/ml)

Options:

A .

2.5 \times 10^{16}

B .

2.5 \times 10^{17}

C .

5 \times 10^{16}

D .

7.5 \times 10^{16}

Answer: Option C
:
C

$\frac{H_{2} O}{6000}$ $\frac{D_{2} O}{1}$

0.01 x

$x = \frac{1 \times 0.01}{6000} = 1.66 \times 10^{- 6}$

$20 g m \to 6.023 \times 10^{23}$

$1.66 \times 10^{- 6} \to x$

$x = \frac{1.66 \times 10^{- 6} \times 6.023 \times 10^{23}}{20} = 5 \times 10^{16}$

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