Question

Which of the following group 2 elements are stored in paraffin ?
A. All group 2 elements
B. All group 2 elements except Be
C. All group 2 elements except Be and Mg
D. All group 2 elements except Be, Mg, and Ca

Answer 1

Correct Answer - C
Group 2 elements are less electropositive than alkali metals and, thus, react slowly with air (or oxygen). Reactivity towards air increases on moving down the group. Be and Mg are kinetically inert to `O_(2)` because of the formation of a thin film of oxide on their surface. Thus, Ca, Sr, and Ba are stored in paraffin.