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प्रश्न
Why is the highest oxidation state of a metal exhibited in its oxide or fluoride only?
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उत्तर
Due to its small size and high electronegativities, oxygen or fluorine elements can oxidize the metal to its higher oxidation state.
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संबंधित प्रश्न
Why +2 oxidation state of manganese is more stable?
Account for the following:
Cr2+ is a strong reducing agent.
How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.
Compare the stability of +2 oxidation state for the elements of the first transition series.
Explain why Mn2+ is more stable than Fe2+ towards oxidation to +3 state. (At. no. of Mn = 25, Fe = 26)
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because ______.
Why EΘ values for Mn, Ni and Zn are more negative than expected?
The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain why?
Mention the type of compounds formed when small atoms like H, C and N get trapped inside the crystal lattice of transition metals. Also give physical and chemical characteristics of these compounds.
The standard electrode potentials of four elements A, B, C and D are – 3.05, – 1.66, – 0.40 and + 0.80. The highest chemical reactivity will be exhibited by
Passing H2S gas into a mixture of Mn2+ and Ni2+, Cu2+, ions in an acidified aqueous solution precipitates.
Which of the following ions has the maximum magnetic moment?
Which of the following transition metal is not coloured?
Which of the following characteristics of transition metals is associated with their catalytic activity?
Account for the following:
Ce4+ is a strong oxidising agent.
Assertion (A): Transition metals have high enthalpy of atomisation.
Reason (R): Greater number of unpaired electrons in transition metals results in weak metallic bonding.
Which of the following transition metals shows +1 and +2 oxidation states?
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.
Why are interstitial compounds well known for transition metals?
For M2+/M and M3+/M2+systems, the EΘ values for some metals are as follows:
| Cr2+/Cr | −0.9 V |
| Mn2+/Mn | −1.2 V |
| Fe2+/Fe | −0.4 V |
| Cr3/Cr2+ | −0.4 V |
| Mn3+/Mn2+ | +1.5 V |
| Fe3+/Fe2+ | +0.8 V |
Use this data to comment upon:
The ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.
