Question

What does an alpha particle $\left( \alpha \right)$ particle consists of:
(a) 2 protons and 2 neutrons only
(b) 2 electrons, 2 protons and 2 neutrons
(c) 2 electrons and 4 protons
(d) 2 protons only

Answer 1

Hint: In this question use the concept that alpha particles are identical to a helium atom. Use the configuration of helium that is $_2H{e^4}$, to comment upon the configuration of alpha particles. This helps get the right answer.

Complete Step-by-Step solution:
As we know $\alpha - $ particle is identical to the helium atom $_2H{e^4}$ that has been stripped of its two electrons, thus an alpha ($\alpha - $particle) consists of 2 protons and 2 neutrons only.
They are emitted from the nucleus of some radionuclides during a form of radioactive decay, called alpha-decay.
So $\alpha - $ particle has 2 protons and 2 neutrons only.
So this is the required answer.
Hence option (A) is the correct answer.

Note – Any element of a periodic table can be represented in the form ${X_Z}^A$ Here X is the element example in the above question it is helium. Z corresponds to the atomic number of this element X and is depicted in subscript in representation. A is called the atomic mass of element X and is depicted in superscript of element X. The number of neutrons of element X can be taken out by the subtraction of rounded mass number and atomic number that is A-Z. The number of protons is equal to the atomic number of element X.