In the following questions two or more options may be correct. Those elements impart colour to the flame on heating in it, the atoms of which require low energy for the ionisation (i.e., absorb energy in the visible region of spectrum). The elements of which of the following groups will impart colour to the flame?

Question

Philoid · Accepted Answer

Group 1 and 2 elements have low ionisation enthalpies as compared to elements of other group. When we provide energy to them then the electrons excite from a lower energy level to a higher. Once they reach the ground state then a particular wavelength is emitted imparting colour to them.