Common Misconceptions
3 min read

The D-and F-Block Elements

- What you are getting from a statement might not be necessarily true. Let us burst some of the common misconceptions
1
D block Elements are Transition Elements
D block elements are the elements which can be found from the third group to the twelfth group of the modern periodic table. They are called so because the last electron enters the d-orbital.
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Transition metals are actually a subset of d-block elements.
For an element to be called transition metal, it should have partially filled d-subshell.
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If we look at the electronic configuration of Zn, Cd and Hg all of them have filled d-orbital.
So, these are d-block elements but not transition elements.
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2
Transition elements form coloured compounds because they have unfilled d orbitals
We know that transition metals form coloured compounds. This is attributed to the fact that they have unfilled d orbitals.
But that is not completely true.
Presence of unfilled d orbital is not enough for colour in transition elements.
The reason being the d orbitals in transition metals are degenerate- they all have the same energy.
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However, when the metal ion forms a complex with other ions or molecules, some of the d orbitals become higher in energy than the others. The difference in d orbital energy levels often corresponds to the wavelength of visible light.
For example, an electron in a lower d level may absorb a quantum of red light and be excited to the higher level. The non-absorbed light is reflected back to our eyes, so we would probably see a blue or green colour.
Thus, the transition of electrons between non-degenerate orbitals is the more accurate explanation behind the coloured transition metal compounds.
3
All d-block elements have high Melting Points   d-block elements have high melting points.
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In general, atoms of transition elements are closely packed by strong metallic bonds leading to high melting and boiling points of the transition elements. But this does not mean all d block elements have high melting point.
Zn, Cd and Hg are soft and have low melting point. In these, formation of strong metallic bond is not possible. As a consequence, they have low melting points.