Give Reasons: Only eight elements are present in period 3, though total number of e- should be present in third shell is 18. Share with your friends Share 0 veena Vasandani answered this Kindly refer to the following link:https://www.meritnation.com/ask-answer/question/the-3rd-period-should-be-having-18-elements-as-per-equation/classification-of-elements-and-periodicity-in-properties/2646745 0 View Full Answer