Question

Which molecules are responsible for the blue colour of the sky ?

• A. \(O_2,N_2\)
• B. \(CO_2,N_2\)
• C. \(N_2,He\)
• D. \(N_2,Cl_2\)

Answer 1

The Correct Option is A

To solve the problem, we need to identify which molecules are responsible for the blue colour of the sky.

1. Understanding the Phenomenon:
The blue color of the sky is due to Rayleigh scattering, a phenomenon where shorter wavelengths of light (like blue and violet) are scattered more than longer wavelengths (like red). However, our eyes are more sensitive to blue light and some violet light is absorbed by the atmosphere, making the sky appear blue.

2. Role of Atmospheric Molecules:
The primary gases in the Earth's atmosphere that cause this scattering are nitrogen (N₂) and oxygen (O₂). These molecules are small enough to scatter shorter wavelengths effectively.

Final Answer:
The correct molecules responsible for the blue color of the sky are \({O_2,\, N_2} \).