Question

In what ratio Cl${}_{17}^{37}$ and Cl${}_{17}^{35}$ be present so as to obtain Cl${}_{17}^{35.5}$?

• A. 1 : 2
• B. 1 : 1
• C. 1 : 3
• D. 3 : 1

Answer 1

The correct option is C 1 : 3

Let $x$% of $Cl$ ${}^{37}$ and $(100-x)$% of $Cl$ ${}^{35}$ be present in $Cl$ ${}_{17}^{35.5}$.

$35.5=$ $\frac{x\times 37+(100-x)\times 35}{100}$

$\Rightarrow x=25$

$\therefore \%$ of $Cl$ ${}^{37}$ $=25$

$\therefore \%$ of $Cl$ ${}^{35}$ $=75$

$\therefore$ Ratio is $=25:75=1:3$.