GENERAL KNOWLEDGE

Detailed explanation-1: -An alpha particle might exist within a heavy nucleus as a different entity. A potential barrier keeps such a particle in the nucleus in constant motion, and there is a tiny but definite chance that the particles will cross through the barrier.

Detailed explanation-2: -Alpha particles (a) are composite particles consisting of two protons and two neutrons tightly bound together (Figure 1). They are emitted from the nucleus of some radionuclides during a form of radioactive decay, called alpha-decay.

Detailed explanation-3: -As with most forms of radiation, alpha particles are emitted from radioactive elements. Alpha particles are relatively heavy and slow compared to their companions, so they pose little danger to humans unless ingested.

Detailed explanation-4: -When a nuclide emits an , the atomic mass decreases by 4 and the atomic number decreases by 2. emission does not result in a change of either atomic mass or atomic number.

Detailed explanation-5: -Answer and Explanation: Alpha decay occurs in heavier elements more commonly because the massive size of the nucleus makes it difficult to balance the repulsive effect of the electromagnetic force when the protons repel each other with the strong nuclear force trying to hold the nucleus together.