Question

questions no. 8,9
Please its very urgent..............

Answer 1

8.
a. oxygen is collected at anode and hydrogen at cathode
b. because in water volume of hydrogen is twice the volume of oxygen.
c. the ionisation of water will slow.
9.Mendeleev’s Periodic Table

I. The elements were arranged according to increased atomic masses.
II. Position of isotopes was not justified.
III. Position of hydrogen was not justified because it resembles both with Alkali metals and Halogens.

Modern Periodic Table

I. The elements were arranged according to increased atomic numbers.
II. There was no problem in the placing of isotopes.
III Hydrogen has been given a unique position due to its resemblance with Alkali metals and Halogens.
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