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Chemistry
The d-and f-Block Elements
explain briefly how 2 state becomes more and more...

Question:
Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

Answer:

The oxidation states displayed by the first half of the first row of transition metals are given in the table below.

	Sc	Ti	V	Cr	Mn
		+2	+2	+2	+2
	+3	+3	+3	+3	+3
Oxidation state		+4	+4	+4	+4
			+5	+5	+6
				+6	+7

It can be easily observed that except Sc, all others metals display +2 oxidation state. Also, on moving from Sc to Mn, the atomic number increases from 21 to 25. This means the number of electrons in the 3d-orbital also increases from 1 to 5.

Sc (+2) = d¹

Ti (+2) = d²

V (+2) = d³

Cr (+2) = d⁴

Mn (+2) = d⁵

+2 oxidation state is attained by the loss of the two 4 selectrons by these metals. Since the number of d electrons in (+2) state also increases from Ti(+2) to Mn(+2), the stability of +2 state increases (as d-orbital is becoming more and more half-filled). Mn (+2) has d⁵electrons (that is half-filled d shell, which is highly stable).

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Question:
Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

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Question: Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?

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Question:
Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?