expalin the followings

Solid PbCl2 is slightly soluble in water?

Sodium sulfate is white in colour while sodium chromate is yellow?

Manganese forms negative oxidation state as well?

Dear Student

Leadchloride is sparingly soluble in Water as you say.

Yes it is .

Dear solubility is a complex process and there is no hard and fast rule that one compound is soluble over other.

There is some factor which decide the solubility.

1). Lattice energy.

If the energy of dissoiciation is less than lattice energy then it will not dissolve.

2).Entropy change.

If entropy is increasing then dissociation favoured.

In conclusion I would say lower solubility of pbcl2 is duw to high lattice energy and greater charge density of Pb2+.