An aqueous solution of $$FeS{O_4},A{l_2}{\left( {S{O_4}} \right)_3}$$ and chrome alum is heated with excess of $$N{a_2}{O_2}$$ and filtered. The materials obtained are :
A.
a colourless filtrate and a green residue
B.
a yellow filtrate and a green residue
C.
a yellow filtrate and a brown residue
D.
a green filtrate and a brown residue
Answer :
a yellow filtrate and a brown residue
Solution :
TIPS/FORMULAE:
Chrome alum is $${K_2}S{O_4}.C{r_2}{\left( {S{O_4}} \right)_3}.24{H_2}O$$
The filtrate is yellow due to $$CrO_4^{2 - }$$ ion and residue is brown due to $$Fe{\left( {OH} \right)_3}.$$
Releted MCQ Question on Inorganic Chemistry >> D and F Block Elements
Releted Question 1
When same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide, the ratio of volume of hydrogen evolved is