Question

i) Name the first and last element of period 2.
ii) What happens to the atomic size of elements while moving down the group?
iii) Which of the element has the greatest reactivity among the halogens?
iv) What is the common feature of the electronic configuration of the elements in Group 17?

Answer 1

i) The first element of period 2 is lithium and the last element is neon.
ii) On moving down the group, the atomic size increases.
iii) Fluorine is the most reactive element in the halogen group because the degree of reactivity of halogens decreases down the group.
iv) The elements that are present in group 17 are halogens. The number of valence electrons remains the same down the group. Therefore, the common feature of the electronic configuration is the 7 electrons present in the outermost shell.