Chapter 4, Problem 9STP

Interpretation Introduction

Interpretation:

The phenomenon likely to occur if an element X has an unstable nucleus due to presence of excess of neutrons.

Concept introduction An atom consists of a dense, thick nucleus that has zero charged subatomic particle, neutron, positively charged subatomic particle proton and is surrounded by negatively charged subatomic particle electron.

Answer to Problem 9STP

Correct answer: Option (c)

Explanation of Solution

Reason for correct option:

Unstable elements generally don't gain protons to balance the neutrons. They mostly have different numbers of protons and neutrons. Thus, option (c) does not likely to occur.

Conclusion

Reasons for incorrect options:

Option (a) All atoms decay and become a stable non-radioactive element.

Option (b) This is possible for an element to not decay thus, it remains unstable. Such unstable elements are known as radioactive elements.

Option (d) Elements lose mass and energy upon decaying as decay is a spontaneous process.