short notes on anomalous behaviour of lithium
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The small size of the lithium atom and the ion make them behave differently from other elements of the same group. However, they do exhibit certain similarities. The ability to form covalent bond due to high electropositive character and the polarising power of Li+ is comparable to that of magnesium ion. This article presents information of the similarities between lithium and its diagonally located element the magnesium.
Reasons for relationship between diagonally located elements
1. As we move down the period the electropositive nature increases, but it decreases as we towards right in a period. Hence, the diagonally located elements have similar electropositive character.
2. 2. As we move down the group, the size of the atom increases and hence, the polarising power decreases. But, the size of the atom decreases as we move right in a period and hence the polarising power increases. So, the diagonally
Because of the above two reasons, the diagonally located elements lithium and magnesium show similarity in properties despite of the difference in the oxidation states.
Similarities of lithium with magnesium and dissimilarities with that of the other members of the group
1. Lithium is a very strong element and is equally strong as magnesium
2. It has high melting and boiling points. The boiling point of lithium is 1330 degree centigrade that is comparable to that of magnesium which is 1100 degrees.
3. Due to small size, the lithium atom has high ionization energy. Hence, it remains inactive to dry air, slowly reactivity with water, liquid bromine and forms a highly stable hydride unlike other alkali metals. All these properties are exactly exhibited by magnesium.
4. As magnesium it forms only monoxides. All the other alkali metal atoms form peroxides and superoxides.
5. Lithium is the only alkali metal that reacts directly with nitrogen forming nitride.
Reasons for relationship between diagonally located elements
1. As we move down the period the electropositive nature increases, but it decreases as we towards right in a period. Hence, the diagonally located elements have similar electropositive character.
2. 2. As we move down the group, the size of the atom increases and hence, the polarising power decreases. But, the size of the atom decreases as we move right in a period and hence the polarising power increases. So, the diagonally
Because of the above two reasons, the diagonally located elements lithium and magnesium show similarity in properties despite of the difference in the oxidation states.
Similarities of lithium with magnesium and dissimilarities with that of the other members of the group
1. Lithium is a very strong element and is equally strong as magnesium
2. It has high melting and boiling points. The boiling point of lithium is 1330 degree centigrade that is comparable to that of magnesium which is 1100 degrees.
3. Due to small size, the lithium atom has high ionization energy. Hence, it remains inactive to dry air, slowly reactivity with water, liquid bromine and forms a highly stable hydride unlike other alkali metals. All these properties are exactly exhibited by magnesium.
4. As magnesium it forms only monoxides. All the other alkali metal atoms form peroxides and superoxides.
5. Lithium is the only alkali metal that reacts directly with nitrogen forming nitride.
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