Question

7.
a)
b)
Define the modern periodic law. Discuss the construction of the long form of the periodic
table. (OR)
) The electronic configuration of the elements X, Y and Z are given below.
A) X=2, 1
B) Y = 2,6
C) Z = 2,8,2
p) Which element belongs to second period ?
q) Among X, Y, Z alkali metal is?
r) Which element belongs to 18h group?
s) What is the valency of element Z?​

Answer 1

the modern periodic law states that the physical and chemical properties of element are a periodic function to their atomic numbers.

1. the hydrogen can be grouped both as alkali metals ( group 1 ) or in halogens group , but it is placed over group 1 .

2. the every element has gained a specific place .

3. the trabsition elements are placed below due to their odd properties .

now , as we know electronic conf. = atomic number

X = 3

Y = 8

Z = 12

1. Z belongs to group 2

2.X is alkali metal

3. Y belongs to group 8

4. Z 's valency is 2

Answer 2

Hiii friend

This is ur answer