Question

In each of the following question match column -I and column -II. Select correct Answer. (a) Bohr atom model (p) fixed for the atom (b) Ionization potential (q) Nucleus (c) Rutherford atom model (r) stationary orbits (d) Thomson atom model (s) In atom positive and Negative charge are distributed uniformly (A) \(\mathrm{a} \rightarrow \mathrm{s}, \mathrm{b} \rightarrow \mathrm{r}, \mathrm{c} \rightarrow \mathrm{q}, \mathrm{d} \rightarrow \mathrm{p}\) (B) \(\mathrm{a} \rightarrow \mathrm{r}, \mathrm{b} \rightarrow \mathrm{p}, \mathrm{c} \rightarrow \mathrm{q}, \mathrm{d} \rightarrow \mathrm{s}\) (C) \(\mathrm{a} \rightarrow \mathrm{p}, \mathrm{b} \rightarrow \mathrm{r}, \mathrm{c} \rightarrow \mathrm{s}, \mathrm{d} \rightarrow \mathrm{q}\) (D) \(\mathrm{b} \rightarrow \mathrm{p}, \mathrm{c} \rightarrow \mathrm{q}, \mathrm{b} \rightarrow \mathrm{r}, \mathrm{d} \rightarrow \mathrm{s}\)

Short answer

The short answer is: (B) a → r, b → p, c → q, d → s

Step-by-step solution

Atomic Models and their Characteristics

There are three atomic models mentioned in column I, namely: 1. Bohr atom model: It proposes the concept of stationary orbits where electrons revolve around the nucleus in fixed paths. 2. Rutherford atom model: It is based on a small positively charged nucleus surrounded by negatively charged electrons. 3. Thomson atom model: It is known as the "plum pudding model," in which positive and negative charges are distributed uniformly throughout the atom.

Matching Column I with Column II

Let's match the atomic models and the ionization potential with their corresponding characteristics. a. Bohr atom model ↔ stationary orbits (r) b. Ionization potential ↔ fixed for the atom (p) c. Rutherford atom model ↔ Nucleus (q) d. Thomson atom model ↔ In atom positive and Negative charge are distributed uniformly (s) The correct matches are: a → r, b → p, c → q, d → s Hence, the correct answer is (B).

Key concepts

Bohr model

The Bohr model was introduced by Niels Bohr in 1913. It represented a significant advancement in understanding atomic structure at the time. In the Bohr model, electrons orbit the nucleus in fixed paths, much like planets around the sun.
Each of these paths is termed a "stationary orbit." In these orbits, electrons do not radiate energy, thus maintaining a stable configuration. Each orbit corresponds to a specific energy level, and electrons can jump between these levels by absorbing or emitting energy in discrete amounts called quanta.
This model explains atomic emission and absorption spectra, marking a significant improvement over previous models. However, Bohr's model primarily applies to hydrogen-like atoms and falls short in explaining the behavior of more complex atomic structures.

Rutherford model

The Rutherford model, conceptualized by Ernest Rutherford in 1911, revolutionized the understanding of atomic structure. Rutherford proposed that the atom consists of a very small, dense, positively charged nucleus surrounded by electrons.
This nucleus holds most of the atom's mass, while the electrons orbit relatively further away, akin to planets orbiting a sun. The classic Rutherford gold foil experiment was crucial; it demonstrated that an atom is mostly empty space with the positive charge concentrated in the nucleus.
While the Rutherford model introduced the concept of a nucleus, it failed to explain why electrons, moving in curved paths, do not lose energy and spiral into the nucleus. This necessitated further advancements, leading to the development of the Bohr model.

Thomson model

The Thomson model, named after J.J. Thomson, is also known as the "plum pudding model". Introduced around 1904, it was one of the earliest models to describe atomic structure.
In this model, an atom is envisioned as a uniform sphere of positively charged matter, within which negatively charged electrons are embedded, resembling plums in a pudding. This distribution of charges was believed to balance the positive and negative charges, resulting in a neutral atom.
Although previous models paved the way for understanding atomic interactions, the plum pudding model was eventually overturned by Rutherford's findings, which highlighted the existence of a centralized nucleus.

Ionization potential

Ionization potential, sometimes known as ionization energy, is a key concept in atomic physics and chemistry. It refers to the minimum energy required to remove an electron from an atom in its gaseous state.
This concept is crucial because it provides insight into the strength of an atom's hold on its electrons. Higher ionization potentials indicate that an electron is more tightly bound to the nucleus, requiring more energy to dislodge it.
The ionization potential varies across different elements and plays a critical role in chemical reactions. It helps chemists understand how atoms interact and bond with each other, as well as the relative reactivity of elements.