Question

An amorphous white salt on strong heating gave a gas which turns lime water
milky and a residue is left which turned yellow when hot and white when cold.
The residue is dissolved in dil. Sulphuric acid by heating to form a clear solution.
To this solution is then added sodium hydroxide solution slowly when a white ppt
is first formed which dissolved completely on excess of sodium hydroxide. Based
on this answer the following questions:
(i) Name the cation and anion present in the amorphous white salt.
(ii) Name the residue formed.
(iii) Write the chemical equation between the residue and dil. Sulphuric acid.
(iv) Identify the white ppt and give the chemical equation when the precipitate
dissolved in excess of ammonia solution.

Answer 1

ஜ۩۞۩ஜ[ ANSWER ]ஜ۩۞۩ஜ

I) Salt might be PbCo3 or ZnCO3.

Cation :-

Pb^+2
or
Zn^+2

Anion:-

Co3^-2

II) The residue formed may be lead oxide OR zinc oxide.

III) єգυατιοи 

ZnCO3 + H2SO4----> ZnSO4 + CO2 + H2O

PbCO3 + H2SO4-----> PbSO4 +CO2 +H2O

iv) The white precipitate may be zinc hydroxide or lead hydroxide.
➡If it is Zinc hydroxide is dissolved in ammonia solution a solution of tetra amine zinc carbonate is formed.
➡If it is lead hydroxide the precipitate remains insoluble.

➶➶➶➶➶[ HOPE IT HELPS ]➷➷➷➷➷