Why Mendeleev's choice of formulae of compounds as the basic for deciding the position of an element in his table was a good one? How would this lead to elements with similar chemical properties being placed in the same group?
Why Mendeleev's choice of formulae of compounds as the basic for deciding the position of an element in his table was a good one? How would this lead to elements with similar chemical properties being placed in the same group?
- Mendeleev developed a Periodic Table of elements where the elements were arranged on the basis of their atomic mass and also on the similarity on chemical properties.
- Among chemical properties, he took the formulae of the hydrides and oxides formed by an element as one of the basic properties of an element for classification.
- He selected oxygen and hydrogen as they are very reactive and formed compounds with most elements.
- He then took 63 cards (as 63 elements were discovered during his time) and wrote properties of each element on one card.
- He arranged them in increasing order of atomic masses and observed periodic reoccurrence of elements with similar properties.
- On this basis, he formulated a Periodic Law, which states that ‘the properties of elements are the periodic function of their atomic masses.
Hence, Mendeleev's choice of formulae of compounds as the basis for deciding the position of an element in his table was good. This leads to elements with similar chemical properties being placed in the same group.
For example, he predicted Eka Boron, Eka Aluminum , Eka Silicon later they were discovered as Scandium, Gallium, and Germanium.
Mendeleev's period table laid the foundation for the modern periodic table.
Mendeleev placed an element with greater atomic mass before the element of lower atomic mass(Due to this, cobalt was placed before nickel in spite of the fact that cobalt has higher atomic mass than nickel) so that elements with similar properties could be grouped together.
- Mendeleev developed a Periodic Table of elements where the elements were arranged on the basis of their atomic mass and also on the similarity on chemical properties.
- Among chemical properties, he took the formulae of the hydrides and oxides formed by an element as one of the basic properties of an element for classification.
- He selected oxygen and hydrogen as they are very reactive and formed compounds with most elements.
- He then took 63 cards (as 63 elements were discovered during his time) and wrote properties of each element on one card.
- He arranged them in increasing order of atomic masses and observed periodic reoccurrence of elements with similar properties.
- On this basis, he formulated a Periodic Law, which states that ‘the properties of elements are the periodic function of their atomic masses.
Hence, Mendeleev's choice of formulae of compounds as the basis for deciding the position of an element in his table was good. This leads to elements with similar chemical properties being placed in the same group.
For example, he predicted Eka Boron, Eka Aluminum , Eka Silicon later they were discovered as Scandium, Gallium, and Germanium.
Mendeleev's period table laid the foundation for the modern periodic table.
Mendeleev placed an element with greater atomic mass before the element of lower atomic mass(Due to this, cobalt was placed before nickel in spite of the fact that cobalt has higher atomic mass than nickel) so that elements with similar properties could be grouped together.
