Find the number of sulphide compounds which are not soluble in hot and dil. HNO_(3) but soluble in aqua regia Ag_(2)S,PbS,HgS,CdS

Find the number of sulphide compounds which are not soluble in hot and

1.	Find the number of sulphide compounds which are not soluble in hot and dil. HNO_(3) but soluble in aqua regia Ag_(2)S,PbS,HgS,CdS
Answer» SOLUTION :`HGS`