Question

1. List any three observations which posed a challenge to mendeleev's periodic law
2. how does the metallic character of elements vary on moving from
a. left to right in a period
b. from top to bottom in a group of the modern periodic table?
Give reason for your answer​

Answer 1

Explanation:

1.mendeleev said that the main fundamental properties is the function of the atomic mass.

he did not give fixed position to hydrogen

he place 2 elements in one block

2. a. the metallic character of elements vary from left to right because the is difference between the electron and the outermost shell.

b. the metallic character of the elements vary while moving from top to bottom in the group of the modern periodic table because the number of shells increase while moving.

Answer 2

the metallic character of elements vary from left to right because the is difference between the electron and the outermost shell. b. the metallic character of the elements vary while moving from top to bottom in the group of the modern periodic table because the number of shells increase while moving.