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प्रश्न
The given graph shows the trends in melting points of transition metals:
Explain the reason why Cr has the highest melting point and manganese (Mn) has a lower melting point.
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उत्तर
Chromium has the greatest number of unpaired electrons in its valence shell [Ar.3d54s1]. These unpaired electrons contribute to the creation of strong metallic bonds. As a result, the elements of the chromium group have extremely high melting points. Manganese has a half-filled d-orbital configuration, which means that all of its electrons spin in the same direction. Mn has a lower melting point because it has fewer interatomic forces of attraction, which are easier to break.
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संबंधित प्रश्न
Account for the following:
E° value for the Mn3+/Mn2+ couple is much more positive than that for Cr3+/Cr2+.
Out of Mn3+ and Cr3+, which is more paramagnetic and why ?
(Atomic nos. : Mn = 25, Cr = 24)
Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{( aq)}}\] ion (Z = 27).
Why do transition metals exhibit higher enthalpy of atomization?
Maximum oxidation state is shown by ____________.
Which of the following ions show higher spin only magnetic moment value?
(i) \[\ce{Ti^3+}\]
(ii) \[\ce{Mn2+}\]
(iii) \[\ce{Fe2+}\]
(iv) \[\ce{Co3+}\]
Why EΘ values for Mn, Ni and Zn are more negative than expected?
While filling up of electrons in the atomic orbitals, the 4s orbital is filled before the 3d orbital but reverse happens during the ionisation of the atom. Explain why?
Assertion: The highest oxidation state of osmium is +8.
Reason: Osmium is a 5d-block element.
The disproportionation of \[\ce{MnO^{2-}_4}\] in acidic medium resulted in the formation of two manganese compounds A and B. If the oxidation state of Mn in B is smaller than that of A, then the spin-only magnetic moment (µ) value of B in BM is ______. (Nearest integer)
