It is known as a group
Hope this helps
Answer:
A)Chlorine and Bromine:
They are both non metal hence they form a covalent bond due to covalent bonding.
B)Potassium and Helium:
Helium ion has a small cationic radius and distorted by the potassium ion due to polarization.
C)Sodium and Lithium:
Both are metals hence they form a metallic bond since they share electrons to the electron cloud.
Non Example: It is not convection because heat is not transferred through a fluid (gas or liquid).
The answer is B, you just check if it is the same on the left and right side
A:
Left side - Right side
2xH - 2xH
1xS - 3xS
4xO - 12xO
2xAl - 2xAl
Therefore A is not correct
B:
Left side - right side
2xK - 2xK
1xCl - 1xCl
1xPb - 1xPb
2xN - 2xN
6xO - 6xO
B is therefore correct as both sides add up
