Question

Calcium ions impart ______ colour to the flame.
A. brick red
B. lilac
C. green
D. blue

Answer 1

Hint: Calcium ion has 20 protons, 18 electrons with the mass of 40 a.m.u. When calcium ion is exposed to the heat that is non-luminous flame then it imparts the colour that is similar to cadmium.

Complete answer:
 - In the given question, we have to identify the correct which is imparted by the calcium ion when it comes in contact with the flame.
- Calcium ion is formed when the two electrons are lost from the calcium atom.
- In the flame test, when the element is exposed to the non-luminous heat then the electron present in the exits to the higher state during which they emit the light.
- The electron exits because they absorb the energy given by the heat.
- Due to which the colour of the flame becomes coloured.
- Similarly, when calcium ion undergoes the flame test then the electrons emit brick red colour due to which the flame also becomes brick red.
- Whereas the lilac colour of the flame is shown by the potassium atoms.
- Green colour of the flame is shown by the atoms such as tungsten.
- Atoms such as arsenic, indium show a blue colour.

Therefore, option A is the correct answer.

Note:
The flame test gives information about the quality of the electron but not about the quantitative data. When the impurity of sodium is present in the molecules then the flame is seen through the cobalt blue glass to neglect the yellow flame of sodium.