when H2S is passed through dilute K2Cr2O7 milkiness appears - Chemistry - The d-and f-Block Elements

Question

when H2S is passed through dilute K2Cr2O7 milkiness appears

Arti Gujrati · Accepted Answer

The chemical reaction that is taking place can be written as
follows:

3H2S + 8HCl +
K2Cr2O7→2CrCl3 +
7H2O+ 3S + KCl

Milkiness in the solution is due to the formation of elemental S in
solution But the colour of the solution is green because of
CrCl3