Question

Potassium salts impart blue colour to the flame.
Answer whether the above statement is true or false.
If true enter 1, else enter 0.

Answer 1

Hint: In chemistry, flame test as an analytical method to find out if certain elements are present in the sample or not. These elements are alkali metals and alkaline earth metals. The elements are mainly present as metal cations.

Complete answer:
> Each element has a characteristic colour. When the chemical composition of each sample is introduced in the flame test there are changes in the colour of the flame. This change in colour helps us to find out which element is present in the given sample.
> When a metal cation is heated in a flame, it results in the excitation of electrons from lower energy level to higher energy level by absorbing the energy in the form of heat. To return to the ground state, the electrons in the excited state emit the visible light.
> Potassium belongs to the alkali metals and present in the Group I of the periodic table. Alkali metals have extra electrons in their valence shells which they can donate easily. When it is burned the electrons are excited and when these electrons are coming back they emit photons of light and these are of different colours depending upon the elements and discrete energy levels.
> Potassium imparts Lilac colour in the flame test not the blue colour.
> So the above statement is False.

Hence, the correct option is 0.

Note: If the concentration of metal cation is very low, it cannot be detected by the flame test. Different samples have different light intensity. Presence of impurities, particularly sodium, will affect the results of the flame test.