Advertisements
Advertisements
प्रश्न
Calculate the number of unpaired electrons in the following gaseous ions:
Mn3+, Cr3+, V3+ and Ti3+. Which one of these is the most stable in an aqueous solution?
Advertisements
उत्तर
| Gaseous ions | Electronic configurations | Number of unpaired electrons |
| Mn3+ | 3d4 4s0 | 4 |
| Cr3+ | 3d3 4s0 | 3 |
| V3+ | 3d2 4s0 | 2 |
| Ti3+ | 3d1 4s0 | 1 |
Of these, Cr3+ is most stable in aqueous solution because it has a half-filled \[\ce{t^3_2g}\] level.
संबंधित प्रश्न
How would you account for the following?
Transition metals exhibit variable oxidation states.
Compare the stability of +2 oxidation state for the elements of the first transition series.
Write the factors which are related to the colour of transition metal ions.
Explain why transition elements form alloys.
Transition metals with highest melting point is ____________.
Which is the most stable oxidation state of iron?
Generally transition elements form coloured salts due to the presence of unpaired electrons. Which of the following compounds will be coloured in solid-state?
Transition elements show high melting points. Why?
When a brown compound of manganese (A) is treated with \[\ce{HCl}\] it gives a gas (B). The gas taken in excess, reacts with \[\ce{NH3}\] to give an explosive compound (C). Identify compounds A, B and C.
The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain why?
When an oxide of manganese (A) is fused with KOH in the presence of an oxidising agent and dissolved in water, it gives a dark green solution of compound (B). Compound (B) disproportionates in neutral or acidic solution to give purple compound (C). An alkaline solution of compound (C) oxidises potassium iodide solution to a compound (D) and compound (A) is also formed. Identify compounds A to D and also explain the reactions involved.
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
Agcl is soluble in NH4OH. The solubility is due to the information of:-
Give reasons for the following statement:
Transition metals and most of their compounds show paramagnetic behaviour.
How is the variability in oxidation states of transition metals different from that of p-block elements?
Assertion (A): Transition metals show their highest oxidation state with oxygen.
Reason (R): The ability of oxygen to form multiple bonds to metals.
Complete the following reaction and justify that it is a disproportionation reaction:
\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]
Describe the oxidising action of potassium dichromate and write the ionic equation for its reaction with iron (II) solution.
