d and f-block elements Flashcards
One shot revision for important reactions and key concepts
Elements of 3d Series
Scandium-Zinc
Elements of 4d Series
Yttrium-Cadmium
Elements of 5d Series
Lanthanum-Mercury
Elements of 6d series
Actinium-Copernicium
Which transition metal does not occur in nature?
Technitium
Coinage metals
Cu,Ag, Au
Physical Properties of transition metals
- good conductors of heat and electricity
- metallic lustre
- strong
- ductile
Trend of atomic radii for d-block elements
Reason : e entering d orbitals shield the nuclear charge incompletely, thus the nuclear charge attracts all the electrons more strongly due to which contraction in size occurs.
- decreases left to right, slightly increases towards the end
- electrons entering d orbitals shield nucleae charge incompletely
nucleus attracts electrons more strongly, hence contraction in size
Ionisation Enthalpy Trend for d-block
- increases left to right, but no appreciable change
- increase in IE is due to increase in nuclear charge
- increase in nuclear charge is balanced by increase in screening effect.
Oxidation States for Sc, Ti, V, Cr
- Sc: +3
- Ti:+2,+3,+4
- V:+2,+3,+4,+5
- Cr:+1,+2,+3,+4,+5,+6
- Mn:+2,+3,+4,+5,+6,+7
Oxidation States for Mn, Fe, Co, Ni, Cu, Zn
- Fe:+2,+3,+4,+6
- Co:+2,+3,+4
- Ni:+2,+3,+4
- Cu:+1,+2
- Zn:+2
What O.S does Mn show in acidic medium and alkaline medium?
- acidic : +2
- alkaline: +4
What is the difference between O.S of d-block elements?
- unlike p block elements, where O.S differs by 2 units, here OS varies by 1unit for mixed oxides.
3 examples of mixed oxides
- Mn3O4
- Fe3O4
- Co3O4
Why do d-block elements show colour?
- metal ion has unpaired electrons
- when electron goes from lower energy orbital to higher energy orbital, if excitation energy lies in visible range then complimentary color is observed.
Which O.S is stable for elements of 3d series?
- +3: Ti,V,Cr
- +2:rest of the elements
-
Ni, Cu, Zn do not show +3 at all
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