Question

Calculate the percent loss in weight after complete decomposition of a pure sample of potassium chlorate, $KCl{O}_3\left(s\right)\to KCl\left(s\right)+O_2\left(g\right)$ :

• A. $39.18$%
• B. $37.25$%
• C. $40.23$%
• D. $42.17$%

Answer 1

The correct option is A $39.18$%

$2KCl{O}_3\left(s\right)\to 2KCl\left(s\right)+3O_2\left(g\right)$

$122.5$ g of substance loses $32\times 1.5=48$ g weight.

So. $\%$ loss is $48\times \frac{100}{122.5}=39.18\%$