Problem 50 - A Complete Resource Book in Chemistry for JEE Main

Question

Loss of a \(\beta\) particle is equivalent to (a) increase of one proton only (b) decrease of one neutron only (c) both (a) and (b) (d) none of these

Step-by-Step Solution

Answer

(c) both (a) and (b)

Step 1: Understand Beta Decay

In beta decay, a neutron in the nucleus changes into a proton while an electron (called a beta particle) is emitted. This process causes the atomic number to increase by one because a neutron becomes a proton.

Step 2: Identify Changes in Atomic Structure

With the emission of a beta particle, the nucleus loses a neutron but gains a proton. This changes the element because its atomic number increases by one, but the mass number remains unchanged since a neutron is converted into a proton.

Step 3: Evaluate the Options

Looking at the options: (a) Increase of one proton only - indicates that the atomic number increases by one. (b) Decrease of one neutron only - implies that a neutron has been removed but not replaced. (c) Both (a) and (b) - fits the situation of beta decay perfectly, as one neutron decreases, and one proton increases. (d) None of these - doesn't fit since option (c) is applicable.

Step 4: Choose the Correct Answer

Option (c) both (a) and (b) is correct because beta decay results in an increase of one proton and a decrease of one neutron simultaneously.

Key Concepts

Neutron to Proton Conversion

In beta decay, a fascinating transformation occurs within an atom's nucleus where a neutron is converted into a proton. Let's break down what's happening here: Neutrons and protons reside in the nucleus of an atom, serving as core components of all atomic structures.
When beta decay occurs:

• A neutron is transformed into a proton.
• This process releases a beta particle, which is essentially an electron ejected from the nucleus.

The importance of this conversion cannot be understated. It plays a pivotal role in the type of element that an atom can become because it changes the fundamental composition of the nucleus. The direct result is an atom with more protons and fewer neutrons. This alteration of the atomic nucleus drives the progression of elements found on the periodic table.

Atomic Number Change

The transformation from neutron to proton during beta decay leads to one very significant change: the atomic number increases by one.
Atomic number refers to the number of protons in the nucleus of an atom. For every neutron that becomes a proton via beta decay, the atomic number jumps up by one, indicating a new element has formed. Yet, despite this increase:

• The mass number—sum of protons and neutrons—remains unchanged since one nucleon is altered, not added or removed.
• This process doesn't add any additional particles to the atom but redistributes the existing ones.

This change is crucial because it signifies a shift to a different element: - For instance, carbon-14 (6 protons) undergoing beta decay becomes nitrogen-14 (7 protons), showcasing exactly how a new element appears as the atomic number rises.

Nuclear Reactions

Nuclear reactions are processes where the nucleus of an atom undergoes modification. Beta decay is a prime example of such a reaction, vividly demonstrating how the internal structure of an atom's nucleus can be rearranged without altering the overall mass of the atom.
During nuclear reactions like beta decay:

• Energy is often released, sometimes in significant amounts.
• The identity of the element involved changes due to alterations within the nucleus.
• New particles, like beta particles and neutrinos, are emitted.

These reactions are driven by fundamental forces and provide insights into atomic stability, radioactivity, and the deeper complexities of particle physics. Beta decay, specifically, illustrates how nuclei achieve balance and isotopic transition through seemingly simple changes that have profound effects on atomic identity.