Question

$I$. When an electric current runs through a sealed tube that contains a very low pressure of hydrogen gas, four different colors of light are produced, red, blue-green, blue-violet, and violet.
$II$. Energy added to the electrons causes them to transition from lower energy levels to higher energy levels. As the electrons return to the lower energy levels they were originally located in, photons of light are emitted.

• A. Statement $I$ is true, Statement $II$ is true
• B. Statement $I$ is true, Statement $II$ is false
• C. Statement $I$ is false, Statement $II$ is true
• D. Statement $I$ is false, Statement $II$ is false

Answer 1

Answer: (A)

Statement $I$ is true, Statement $II$ is true

As the electric current is passed, electrons absorb energy and get excited to various higher excitation state resulting in the different colours of light in the tube when they return to the lower excitation state due emission of photons of light.

Therefore, both statements are true.