Question

Which of these electronic transitions in hydrogen is exothermic? question 11 options:

Answer 1

The electronic transition in a hydrogen atom from $\boxed{{\text{a}}{\text{. n = 3 to n=2}}}$ is an exothermic process.

Further explanation:

An electronic transition is a process when an electron undergoes emission or absorption from one energy level to another energy level.

When an electron undergoes a transition from lower energy to the higher energy level then it requires energy to complete the process. Thus this transition is an absorption process.

When an electron undergoes a transition from higher energy to lower energy level then it emits the energy to complete the process. Thus this transition is an emission process.

The formula to calculate the difference between two energy levels of a hydrogen atom is,

 $\Delta E={R_{\text{H}}}\left({\frac{1}{{{{\left({{{\text{n}}_{\text{i}}}}\right)}^2}}}-\frac{1}{{{{\left({{{\text{n}}_{\text{f}}}}\right)}^2}}}}\right)$

Where,

$\Delta E$  is the energy difference between two energy levels.

${R_{\text{H}}}$  is a Rydberg constant.

${{\text{n}}_{\text{i}}}$  is the initial energy level of transition.

${{\text{n}}_{\text{f}}}$  is the final energy level of transition.

The endothermic reactions are the reaction that absorbs heat from its surroundings. The exothermic reactions are reactions that release the heat to its surroundings.

Solution:

Classification of transitions

1. In the transition from n=1 to n=3, electron goes from lower energy level (n=1) to higher energy level (n=3). Therefore, it needs to absorb the energy. Hence, this transition is classified as an absorption process. Since absorption process required the energy to complete the process thus it is an endothermic process.

2. In transition from n=3 to n=2, electron goes from higher energy level (n=3) to lower energy level (n=2), therefore, it needs to emit the energy. Hence, this transition is classified as an emission process. Since emission process releases the energy to surrounding thus it is an exothermic process.

Learn more:

1. Identify oxidation numbers: brainly.com/question/2086855

2. Calculation of volume of gas: brainly.com/question/3636135

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Atomic structure

Keywords: transition, a hydrogen atom, transition from n=1 to n=3, transition from n=3 to n=2, hydrogen, absorption process, emission process, endothermic and exothermic process.

Answer 2

The answer is Option a Reason The electron is moving closer to the nucleus. That is, in other words, it is moving to a lower energy level and will, therefore, give out energy When a transition gives out energy or in other terms it emits heat, it's exothermic. Hence the option a.