Question

. (i) State the number of elements in Period 1, Period
2, and Period 3 of the periodic table. Name
them.
(ii) What is the common feature of the electronic
configuration of the elements at the end of Period
2 and Period 3 ?
(iii) If an element is in Group 17, it is likely to be
[
metallic/non-metallic) in character, while
with one electron in its outermost energy level
(shell), then it is likely to be [metallic/non-
metallic].
iv) In Period 3, the most metallic element is
(sodium/magnesium/aluminium).​

Answer 1

Answer:

In period 1 there are 2 element

Hydrogen and Helium

In period two there are 8 elements

li,Be, B,C,N,O,Ne

In period two there are 8 elements

Na, Mg,Al, Si ,P,S,Cl,Ar

They have two electrons in their outermost shell

They have three electrons in their outermost shell

iii.) non metallic,non metallic

iv.) sodium.