Question

Arrange the following compounds in the correct order of percentage of metallic element.
(a) Potassium hydroxide (b) Potassium carbonate
(c) Potassium bicarbonate (d) Potassium sulphide

• A. a > b > c > d
• B. b > a > c > d
• C. c > b > a > d
• D. d > a > b > c

Answer 1

Answer: (D)

d > a > b > c

A) %age of K in KOH = $\frac{39}{56}\times 100$ = 69.64%
B) %age of K in $K_{2}C{O}_3$ = $\frac{78}{138}\times 100$ = 56.5%
C) %age of K in $KHC{O}_3$ = $\frac{39}{100}\times 100$ = 39%
D) %age of K in $K_{2}S$ = $\frac{78}{110}\times 100$ = 70.9%
Therefore the correct answer is (D)