In a NiCd battery, a fully charged cell is composed of nickelic hydroxide. Nickel is an element that has multiple oxidation states. Assume the following proportions of the states:

X 0 2 3 4

p (X) p 0.23 0.35 0.20

(a) The missing probability p is equal to?

The missing probability p = 0.22.

Step-by-step explanation:

A fully charged cell is composed of nickelic hydroxide in a NiCd battery.

Nickel is known to be such an element that it has multiple oxidation states.

The proportions of the states are given as following.

X p (X)

0 p

2 0.23

3 0.35

4 0.2

The total probability of an event, which in this case, is the event that Nickel has oxidation states of either 0, 2, 3 or 4, is always equal to 1.

Therefore we can write p + 0.23 + 0.35 + 0.2 = 1

Therefore p = 1 - (0.23 + 0.35 + 0.2) = 1 - 0.78 = 0.22

The missing probability p = 0.22.