Question

Which of the following metalsts diamagnetic?

A. Potassium
B. Cesium
C. Barium
D. Lithium

Answer 1

Option C. Barium is the correct answer .

Barium is diamagnetic. Diamagnetic materials are not attracted to magnets, and they have all their electron spins paired, resulting in no net magnetic moment. Barium, being an alkali earth metal, has paired electron spins, making it diamagnetic.

Step-by-step explanation:

This question can be answered by writing the electron configuration of the all 4 elements . Element which will have all electrons spin paired then that element will be diamagnetic otherwise paramagnetic.

A. Lithium

Electron configuration : [ He ] 2s¹

Symbol in the square bracket represents the nobel gas electron configuration.

Since it has electron in 2s orbital which is not paired . So it will not be diamagnetic . It will be paramagnetic . So Option A is incorrect.

B. Potassium

Electron configuration : [Ar] 4s¹

For the same reason as in case of A , this cannot ve diamagnetic because it has electron in 4s orbital which is not paired .

C. Barium

Electron configuration : [Xe]6s²

Since electron in 6s orbital is paired because s orbital can accommodate maximum two electron , and when two electrons are accommodated then both electrons will be paired . Hence it will be diamagnetic . So option C is the correct answer .

D. Cesium

Electron configuration : [Xe]6s¹

For the same reason as in case of option A and B , this element is paramagnetic .

Answer 2

Lithium is the metal among the list that is diamagnetic due to its filled shell configuration with no unpaired electrons when it is in its metallic form.

option d is the correct

Step-by-step explanation:

The question asks which of the provided metals is diamagnetic. Diamagnetism is a property of materials that have no unpaired electrons and are thus not attracted to a magnetic field but rather slightly repelled by it. Among the metals listed, lithium is the one that is diamagnetic.

Lithium atoms have a [He]2s1 electron configuration; when they form lithium metal, they lose one electron, resulting in a filled shell configuration with no unpaired electrons. Thus, lithium, when in its metallic form which is commonly encountered, exhibits diamagnetic behavior.

Other metals on the list, such as potassium, cesium, and barium, are alkali or alkaline earth metals and typically have at least one unpaired electron in their metallic state, making them paramagnetic. Paramagnetic materials have unpaired electrons and are attracted to magnetic fields. Therefore, potassium, cesium, and barium are not the correct answers as they are not diamagnetic.