Chemistry, 29.01.2020 08:50, Juanga122

Explain why the first ionization energy of krypton is greater than the first ionization energy of bromine

Answers: 1

Show answers

Answers

The atomic radius of krypton is similar to that of bromine. However, the effective nuclear charge of krypton is greater than that of bromine.

Explanation:

Ionizing an atom require moving an electron from the electron cloud of the atom to a point infinitely far away from the atom. The first ionization energy of this atom is the energy change in this process.

The electron and the nucleus are oppositely-charged. There is an electrostatic force between the two. Removing the electron requires overcoming this attraction. The size of the energy input depends on the electrostatic potential energy of the electron (the gravitational potential energy is much smaller than the electrostatic potential energy.) The separation between the electron and the nucleus is much larger than their radii. Both objects can be considered as point charges. Coulomb's Law gives the electrostatic potential energy of the two point charge that are close to each other.

$\displaystyle \text{Electrostatic Potential Energy} = -\frac{k\cdot (q_1\cdot q_2)}{r}$ ,

where

is Coulomb's constant, q_1

and

are the two charges, and

is the separation between the two charges.

Krypton and bromine are right next to each other in the same period. Their atomic radii will be similar to each other. The separation between the outermost electron and the nucleus will also be similar for the two elements.

The first charge q_1 can be the electron. However, data show that for elements after helium, the second charge q_2 is smaller than the sum of charges on all protons in the nucleus. It turns out that the inner shell electrons (all of which are also negative) repel electrons in the outermost valence shell. The effective nuclear charge $Z_\text{eff}$ of a neutral atom is approximately the same as the number of protons minus the number of non-valence electrons. That number will be slightly larger for krypton than for bromine. As a result, the electrostatic potential energy on a 4p (the outermost orbital for both Kr and Br) electron of krypton will be more negative than that on a 4p electron in bromine. Removing that electron will take more energy in Kr than in Br. The first ionization energy of Kr is hence greater than that of Br.

answered: Guest

jjj

answered: Guest

Fine out your self ponk

Other questions on the subject: Chemistry

Chemistry, 21.06.2019 19:30, solomander4

The electromagnetic force acts between what

Answers: 1

continue

Chemistry, 22.06.2019 18:00, ameliaxbowen7

Heat is the total potential energy of a substance that can be transferred. true false

Answers: 1

continue

Chemistry, 22.06.2019 21:00, thebasedgodchri

Need what is special about water as a compound? how does water regulate climate? what drives water evaporation? why is the water vapor fresh water when it rises from the ocean? why might freshwater in the form of snow take longer to enter the water cycle again than liquid precipitation? what is an aquifer? what role do people play in the water cycle? plz just answer as many as you can ! thx if you !

Answers: 1

continue

Chemistry, 22.06.2019 21:00, ciel8809

Which answer tells the reason the earth’s climate is getting warmer? too many animals are becoming extinct. large glaciers are melting in antarctica. the earth is moving closer to the sun. driving cars gives off gases that trap heat in the atmosphere.

Answers: 1

continue

Do you know the correct answer?

Explain why the first ionization energy of krypton is greater than the first ionization energy of br...