Question

Beryllium and magnesium do not give colour to flame whereas other alkaline earth metal do so . why

Answer 1

When alkalike metals are heated on a Bunsen flame the electrons get excited to higher energy level due to taking in of energy. When these electrons return to ground state they emit the extra energy in form if radiations which are are in the visibility spectrum hence we can see a flame colour for each of themHowever no charactoristic colour is shown by magnesium or berrilyium since their atoms have a smaller size and due to small size the nuclear charge experienced by the electrons is greater. Therefore greater amount of energy is needed for excitation of electron to higher energy level which is not provided by the buns end flame.

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