Q. The molecular formula of potash alum is
A) $KAl_{2}S_{4}H_{48}O_{40}$
B) $K_{2}Al_{2}S_{4}H_{48}O_{39}$
C) $K_{2}Al_{2}S_{4}H_{48}O_{40}$
D) $KAl_{2}S_{4}H_{48}O_{40}$
Explanation
(c)
The composition of potash alum is
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ K_{2}SO_{4}\ .\ Al_{2}\left( SO_{4} \right)_{3}\ .\ 24H_{2}O\$
or $\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {\ \ K}_{2}Al_{2}S_{4}H_{48}O_{40}$
It is a double salt of potassium sulphate and aluminium sulphat.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.