मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

Explain Why is Fe3+ More Stable than Fe2+? - Chemistry

Advertisements
Advertisements

प्रश्न

Explain why is Fe3+ more stable than Fe2+?

Advertisements

उत्तर

Electronic configuration of Fe2+ : 1s2 2s2 2p6 3s2 3p6 3d6
Electronic configuration of Fe3+ : 1s2 2s2 2p6 3s2 3p6 3d5 
Due to the presence of half filled ‘d’ orbital, Fe3+ is more stable than Fe2+.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
2014-2015 (October)

APPEARS IN

संबंधित प्रश्‍न

Why do interstitial compounds have higher melting points than corresponding pure metals?


How would you account for the following? 

Transition metals exhibit variable oxidation states.

 


Calculate magnetic moment of  `Fe_((aq))^(2+) ion (Z=26).`


Account for the following: 

Cr2+ is a strong reducing agent.


Account for the following:

Cu+2 salts are coloured, while Zn2+ salts are white.


The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co

Answer the following: Which element has the highest m.p?


Explain briefly how +2 state becomes more and more stable in the first half of the first row transition elements with increasing atomic number?


What are the characteristics of the transition elements and why are they called transition elements? 


Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:

Electronic configurations


What can be inferred from the magnetic moment value of the following complex species?

Example Magnetic Moment (BM)
K2[MnCl4] 5.9

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?


Give reasons: Sc3+ is colourless in aqueous solution whereas Ti3+ is coloured.


Two metallic elements A and B have the following standard oxidation potentials: A = 0·40v B = - 0·80v. What would you expect if element A was added to an aqueous salt solution of element B? Give a reason for your answer.


Read the passage given below and answer the following question:

The transition metals when exposed to oxygen at low and intermediate temperatures form thin, protective oxide films of up to some thousands of Angstroms in thickness. Transition metal oxides lie between the extremes of ionic and covalent binary compounds formed by elements from the left or right side of the periodic table. They range from metallic to semiconducting and deviate by both large and small degrees from stoichiometry. Since electron bonding levels are involved, the cations exist in various valence states and hence give rise to a large number of oxides. The crystal structures are often classified by considering a cubic or hexagonal close-packed lattice of one set of ions with the other set of ions filling the octahedral or tetrahedral interstices. The actual oxide structures, however, generally show departures from such regular arrays due in part to distortions caused by packing of ions of different size and to ligand field effects. These distortions depend not only on the number of d-electrons but also on the valence and the position of the transition metal in a period or group.

In the following questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices on the basis of the above passage.

Assertion: Cations of transition elements occur in various valence states.

Reason: Large number of oxides of transition elements are possible.


Why is \[\ce{HCl}\] not used to make the medium acidic in oxidation reactions of \[\ce{KMnO4}\] in acidic medium?


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.


Although fluorine is more electronegative than oxygen, but the ability of oxygen to stabilise higher oxidation states exceeds that of fluorine. Why?


Assertion: Separation of \[\ce{Zr}\] and \[\ce{Hf}\] is difficult.

Reason: Because \[\ce{Zr}\] and \[\ce{Hf}\] lie in the same group of the periodic table.


Assertion (A): Cu cannot liberate hydrogen from acids.

Reason (R): Because it has positive electrode potential.


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.


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.


It has been observed that first ionization energy of 5 d series of transition elements are higher than that of 3d and 4d series, explain why?


Which of the following is non-metallic?


On strong heating AgNO3, the gases evolved are:-


The product of oxidation of I with \[\ce{MnO^{-}4}\] in alkaline medium is:-


Among the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other in:-


Which of the following characteristics of transition metals is associated with their catalytic activity?


The trend of which property is represented by the following graph?


Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:

Ionisation enthalpies


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×