Question

19. (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:

i . Period 1 : 2

period 2 : 8

period 3 : 8

Explanation:

ii . at the end of the period every element contain 8 electron at the last orbit except He that contains 2 election.

iii.non metalic.

iv . sodium

Answer 2

Answer:

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