The atomic radii of li, na, and rb are 152 pm, 186 pm, and 244 pm, respectively. what is a reasonable estimate for the atomic radius of k? group of answer choices 231 pm
105 pm
268 pm
163 pm

The radii of potassium is 231 pm

Explanation:

Atomic radii trend along group:

As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.

The given elements are present in same group i.e group one,

Li     152 pm

Na    186 pm

K

Rb    244 pm

The radii of potassium must be greater than sodium and smaller than rubidium.

Thus the value must be between 186 pm - 244 pm

it means the radii of potassium is 231 pm.

This type of reaction is known as double displacement reaction or metathesis reaction.

Example:

FeSO  

4

​  

+CuCl  

2

​  

⟶FeCl  

2

​  

+CuSO  

4

​

Explanation: