Question

Two elements $\left(X\right)and\left(Y\right)$ combine to form compound $\left(A\right)and\left(B\right)$. For the fixed mass of $\left(X\right)$, masses of $\left(Y\right)$ combine are in $3:7$ ratio. If in $\left(A\right)$, $4g$ of $\left(X\right)$ combine with $12g$ of $\left(Y\right)$, then in $\left(B\right)$, $8g$ of $\left(X\right)$ will combine with _______ $g$ of $\left(Y\right)$

• A. $8$
• B. $56$
• C. $28$
• D. $24$

Answer 1

The correct option is B $56$

Since for the fixed mass of $\left(X\right)$ masses of $\left(Y\right)$ combine are $3:7$

Suppose mass of $\left(X\right)$ is fixed in $\left(A\right)$ and $\left(B\right)$ that is $=4g$

$\therefore$ in the formation of $\left(A\right),4\left(g\right)\left(X\right)$ combine with $12g$ of $Y$

$\therefore$ in the formation of $\left(B\right)4g$ will combine with $28g$ of $Y$.

According to mass ratio of $Y$.

If $4g\left(X\right)$ combine with $=28gY$

Then $8g\left(X\right)$ will combine with $=\frac{28}{4}\times 8gY=56gY$