Question

How many electrons should we expect to see associated with the lowest energy peak in the photoelectron spectrum of the element bromine (br)?

Answer 1

Ans: 7 electrons

The peaks in a photoelectron spectrum correspond to the binding energy of electrons in a given substance. The lower energy peaks represent the binding energy of the outer or valence electrons whereas the higher energy peaks correspond to that of the inner and core electrons.

The atomic number of bromine is 35. The electron configuration would be:

Br[35] =[ 1s²2s²2p⁶3s²3p⁶3d¹⁰]4s²4p⁵

The valence electron configuration is:

Br[35] = 4s²4p⁵

there are 7 valence electrons, thus the lowest energy peak would be associated with  7 electrons.

Answer 2

There are five electrons associated with the lowest energy peak in bromine photoelectron spectrum.

Further explanation:

Photoelectron spectroscopy:

The photoelectron spectroscopy is a spectroscopy that is used to determine the electronic configuration of the elements.

In other words, this method is very helpful in identifying the electronic structure of the atom. In this method, sample of atoms is exposed under the high energy radiation such as UV or X-rays. This bombardment of high energy rays causes the ejection of various electrons. Then photoelectron spectrometer measures the number of electron ejected and their kinetic energy.

For example, ground state configuration of lithium is $1{s^2}2{s^1}$ . This shows two peaks in photoelectron spectrum. These two peaks representing two subshells of lithium atom. The first peak is related to the 1 electron with lower binding energy while the second peak is related to the two electrons with higher binding energy.

The atomic number of bromine is 31 thus, the ground state of electronic configuration of bromine (Br) is $\left[ {{\mathbf{Ar}}}\right]{\mathbf{4}}{{\mathbf{s}}^{\mathbf{2}}}{\mathbf{4}}{{\mathbf{p}}^5}$ .

Since the lowest energy peak is related to the lowest binding energy, and 4p electrons have lowest binding energy. Therefore, there are five electrons associated with the lowest energy peak in bromine photoelectron spectrum.

Learn more:

1. The neutral element represented by the excited state electronic configuration: brainly.com/question/9616334

2. Number of covalent bond formed by carbon: brainly.com/question/5974553

Answer details:

Grade: Senior school

Subject: Chemistry

Chapter: Photoelectron spectroscopy

Keywords: Photoelectron, spectroscopy, photoelectron spectrum, bromine, lowest energy peak, element, electrons, electronic configuration of bromine.