Question

Which of the following does not contain material particles?
A. $\alpha $ -rays
B. $\beta $ -rays
C. $\gamma $ -rays
D. Anode rays

Answer 1

Hint: The radioactive nuclides undergo decay to give alpha, beta, gamma, X-rays. All these rays have different energy, different characteristics. Some of these rays are made from one material or atom and some are made from only higher energy radiation.

Complete Step by Step Answer:
$\alpha $ -rays consist of $\alpha $ particles. The alpha particles are actually helium atoms. Helium atoms have a mass number of $4$ and atomic number of $2$ . Alpha particles make stable nuclei. Thus $\alpha $ -rays contain material particles.

$\beta $ -rays consist of beta particles. The beta particles are actually high energetic electrons. Electrons are negatively charged particles of the nucleus that revolve around the nucleus. Due to the presence of positively charged protons in the nucleus an atom remains stable with negatively charged electrons.. Thus $\beta $ -rays contain material particles.

$\gamma $ -rays are not material particles. It is a high energetic electromagnetic radiation consisting of a packet of energy. It is emitted due to radioactive disintegration of radioactive nuclide. Anode rays contain material particles. It is a high energetic electromagnetic radiation consisting of a packet of positive ions. It is emitted from gas discharge tubes. Thus it contains positive materials.
Thus the correct option is C.

Note: Alpha particles as a building block make a nuclide exceptionally stable. These rays are emitted due to disintegration of unstable nuclide or radioactive nuclide. These rays have higher energy.