Chlorophyll extracted from the crushed green leaves was dissolved in water to make $2 \mathrm{~L}$ solution of Mg of concentration $48\, \mathrm{ppm}$. The number of atoms of $\mathrm{Mg}$ in this solution is $x \times 10^{20}$ atoms. The value of $x$ is ___________. (Nearest Integer)
(Given : Atomic mass of $\mathrm{Mg}$ is $$24 \mathrm{~g} \mathrm{~mol}^{-1} ; \mathrm{N}_{\mathrm{A}}=6.02 \times 10^{23} \mathrm{~mol}^{-1}$$ )
Answer (integer)
24
Solution
In $2 \mathrm{L} \rightarrow 96 \,\mathrm{mg}$ of $\mathrm{Mg}$
<br/><br/>
Number of atoms of $\mathrm{Mg}=\frac{96 \times 10^{-3}}{24} \times \mathrm{N}_{\mathrm{A}}$
<br/><br/>
$$
\begin{aligned}
&=4 \times 10^{-3} \times 6 \times 10^{23} \\
&=24 \times 10^{20}
\end{aligned}
$$
<br/><br/>
$x=24$
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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