Inorganic chemistry is a in which we study the properties , synthesis , structure and reactions of inorganic compounds.

Topic :-

1. Periodic Table
2. Atomic Structure
3. s – block , p – block , d – block and f – block
4. Electronic Configuration
5. Classification of Elements
6. Hydrogen
7. Environmental Chemistry
8. Bio inorganic Chemistry
9. Instrumental Methods of Analysis
10. Analytical Chemistry

1. Dobereiner’s Triads
2. Newland’s Law of Octaves
3. Mendeleev’s Periodic Table
4. Modern Periodic Table

Dobereiner’s Triads :-

According to Dobereiner’s , three elements are placed in group and in this triads the atomic mass of the middle element is equal to the atomic mass of the other two elements.

1. ₃Li⁷ , ₁₁Na²³ , ₁₉K³⁹

= =23

2. ₂₀Ca⁴⁰ , ₃₈Sa⁸⁸ , ₅₆Ba¹³⁷

=   =   =  88.5

Dobereineris classification :-

It foiled to organize all the elements in to triads of elements with similar chemical properties.

Dobereiner could identify only three elements at that time .

According to Newlands law of octaves , when atoms are arranged in increasing order of that mass, then the properties of each 8th element are equal to the first element property .

1. First element – Hydrogen , Last element – Thaorium
2. This rule was valid only till Calcium
3. This rule was based on the seven notes of music
4. This rule is valid only for Light element
5. Co, Ni and Ce, La elements were kept Together

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The properties of elements are a periodic function of their atomic masses.

There were 63 elements during Mendeleev’s time.

Noble gases were not known at that time. So there no group of noble gases.

There were 7 periods and 8 groups in periodic table.

He selected hydrogen and oxygen as they are very reactive and formed compound with most elements.

Mendeleev’s periodic law predicated the existence of some elements that has not been discovered at that time.

Could predict the properties of Several elements on the basis of their position in the periodic table.

Could accommodate noble gases when they were discovered.

The position of isotopes could not be explained.

Wrong order of atomic masses of same elements could not be explained.

A correct position could not be assigned to hydrogen in the periodic table.