Question

Which of these elements in group 1A has the largest atomic radius? Cesium, Rubidium, Potassium, or Sodium?

Answer 1

Cesium is the element in group 1A that has the largest atomic radius, with the number of 225.
Rubidium has 211, Potassium 196, and Sodium 154.

Answer 2

Answer: Option (a) is the correct answer.

Explanation:

It is known that when we move down a group then there occurs an increase in the size elements due to the addition of more number of electrons into new shells.

Hence, it means that atomic radius of the elements also increases.

For the given group 1A elements, sodium is at the top so it has smaller atomic radius whereas cesium is at the bottom. Therefore, cesium has the largest atomic radius.

Thus, we can conclude that cesium elements in group 1A has the largest atomic radius.