Question

Which of the following is odd one out?
[A] Cobalt
[B] Calcium
[C] Chlorine
[D] Oxygen​

Answer 1

Answer:

C] chlorine because there is a

Answer 2

Option [A], Cobalt is the odd one out.

• Transition elements are the elements from group 3 to group 12 of the periodic table.

• Cobalt is a transition element belonging to group 9 of the periodic table.

• Calcium is a non-transition element belonging to group 2 of the periodic table.

• Chlorine is a non-transition element belonging to group 17 of the periodic table.

• Oxygen is a non-transition element belonging to group 16 of the periodic table.

• Therefore, we see that, among all the options given, cobalt is the only transition element, whereas, others are non-transition elements. Hence, cobalt is the odd one out.