color of compounds

The black colored compounds are

The gas obtained by roasting of sulphide ore is reacted with acidified potassium dichromate. A green colored compound 'X' is formed. The compound X can be :

Red colored compound , hemoglobin present in blood contains 0.355% Fe (AM = 56u) If four atoms of Fe are present per molucule of hemoglobin, its molecular mass would be

(a) A blackish brown coloured solid 'A' when fused with an alkali metal hydroxide in the presence of air, produces a dark green colored compound 'B' which upon electrolytic oxidation in alkaline medium gives a dark purple coloured compound 'C'. Identify A,B and C and write the reactions involved. (b) What happesn when acidic solution of green compound (B) is allowed to stand for sometime? Give the equation involved. What is this type of reaction called ?

Formation Of Colored Compounds

The correct order of intensity of colors of the compounds is :

Which of the following compounds are red in color ?

Which of the following compounds does not give Prussian blue color during Lassaigne's test for the detection of nitrogen?