Why is heart wood dark in colour?

A shiny brown-coloured element 'X' on heating in air becomes black in colour. Name the element 'X' and the black-coloured compound formed.

Why Chloroform is preserved in dark coloured glass bottle?

What is the grass-green colour of green algae due to?

Distinguish between heart wood and sap wood.

A blackish brown coloured solid 'A' when fused with alkali metal hydroxides in presence of air, produces a dark green coloured compound 'B' which on electrolytic oxidation in alkaline medium gives a dark purple coloured compound 'C' Identify A, B and C and write the reactions involved.

Why does the sky appear dark instead of blue to an astronaut?

Why do members of Phaeophyceae vary in colour from olive green to various shades of brown?