Why common salt is black in colour?

Answer 1

Not sure of the detail your after, but the simplest reason is because different salts have different elements in them, and since all atoms have a unique spectrum, they all emit different colours, the salts are based on the metals since metals tend to emit in the visible spectrum.

Hence different salts have different metals which absorb energy from the flame and then give it off in a distintive series of jumps the electron will make from the excited state to it's ground state. This series is specific to the atom, and hence a different colour to that of the other salts.

Answer 2

Common salt is a white powder, large crystals are transparent with no color. Sodium chloride does not have energy bands low enough to absorb visible light. Coloured salts are generally transition metals which have these lower energy bands.

Answer 3

Common salt is typically white in color because it consists of sodium chloride crystals, which are inherently colorless. If salt appears black, it may have been contaminated with impurities or minerals that give it a darker color, such as iron oxide or organic matter. Salt should ideally be white, so black salt may not be suitable for consumption.

Answer 4

well it depends on where the salt came from or what substances it has

Answer 5

Table salt (NaCl) is white; only extremely impure salt is coloured.

Answer 6

They are colored because they contain some impurities.