Advertisements
Advertisements
प्रश्न
On the basis of the figure given below, answer the following questions:
- Why Manganese has lower melting point than Chromium?
- Why do transition metals of 3d series have lower melting points as compared to 4d series?
- In the third transition series, identify and name the metal with the highest melting point.
Advertisements
उत्तर
- Manganese is having lower melting point as compared to chromium, as it has highest number of unpaired electrons, strong interatomic metal bonding, hence no delocalisation of electrons.
- There is much more frequent metal-metal bonding in compounds of the heavy transition metals i.e 4d and 5d series, which accounts for lower melting point of 3d series.
- Tungsten
APPEARS IN
संबंधित प्रश्न
Why do interstitial compounds have higher melting points than corresponding pure metals?
To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.
Following are the transition metal ions of 3d series:
Ti4+, V2+, Mn3+, Cr3+
(Atomic numbers: Ti = 22, V = 23, Mn = 25, Cr = 24)
Answer the following:
1) Which ion is most stable in an aqueous solution and why?
2) Which ion is a strong oxidising agent and why?
3) Which ion is colourless and why?
Dissociation of H2S is suppressed in acidic medium.
Why EΘ values for Mn, Ni and Zn are more negative than expected?
Out of \[\ce{Cu2Cl2}\] and \[\ce{CuCl2}\], which is more stable and why?
When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, a yellow solution of compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C) can be crystallised from the solution. When compound (C) is treated with KCl, orange crystals of compound (D) crystallise out. Identify A to D and also explain the reactions.
Photographic film and plates have - au essential ingredient of
The complex showing a spin-span magnetic moment of 2.82 B.M. is :-
A coordination compound has the formula \[\ce{CoCl3.4NH3}\]. It precipitates silver ions as AgCl and its molar conductance corresponds to a total of two ions.
Based on this information, answer the following question:
- Deduce the structural formula of the complex compound.
- Write the IUPAC name of the complex compound.
- Draw the geometrical isomers of the complex compound.
