Advertisements
Advertisements
Question
Calculate magnetic moment of `Fe_((aq))^(2+) ion (Z=26).`
Advertisements
Solution
Data: Fe2+
Z=26
Electronic configuration of
`Fe^(2+)=1s^2 2s^2 2p^6 3s^2 3p^6 4s^@3d^6`
No. of unpaired electrons = 4
To find: Magnetic moment = u
Formula: `u=sqrt(n(n+2))B.M.`
Solution: `u=sqrt(4(4+2))`
`=sqrt24`
u = 4.90 B.M.
APPEARS IN
RELATED QUESTIONS
Why is Sc3+ colourless while Ti3+ coloured? (Atomic number Sc = 21, Ti =22)
How would you account for the following : Transition metals form coloured compounds
How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?
What are the characteristics of the transition elements and why are they called transition elements?
Compare the stability of +2 oxidation state for the elements of the first transition series.
Which metal in the first series of transition metals exhibits +1 oxidation state most frequently and why?
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?
Write down the number of 3d electrons in the following ion:
Cu2+
Indicate how would you expect the five 3d orbitals to be occupied for this hydrated ions (octahedral).
Give reasons Iron has the higher enthalpy of atomization than that of copper.
Give reasons: Sc3+ is colourless in aqueous solution whereas Ti3+ is coloured.
The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10
Why do transition metals exhibit higher enthalpy of atomization?
Maximum oxidation state is shown by ____________.
Generally transition elements form coloured salts due to the presence of unpaired electrons. Which of the following compounds will be coloured in solid-state?
When \[\ce{KMnO4}\] solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because ______.
A solution of \[\ce{KMnO4}\] on reduction yields either a colourless solution or a brown precipitate or a green solution depending on pH of the solution. What different stages of the reduction do these represent and how are they carried out?
The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain why?
EΘ of Cu is + 0.34V while that of Zn is – 0.76V. Explain.
Match the solutions given in Column I and the colours given in Column II.
| Column I (Aqueous solution of salt) |
Column II (Colour) |
| (i) \[\ce{FeSO2.7H2O}\] | (a) Green |
| (ii) \[\ce{NiCl2.4H2O}\] | (b) Light pink |
| (iii) \[\ce{MnCl2.4H2O}\] | (c) Blue |
| (iv) \[\ce{CoC12,6H2O}\] | (d) Pale green |
| (v) \[\ce{Cu2 Cl2}\] | (e) Pink |
| (f) Colourless |
Identify the metal and justify your answer.
Carbonyl \[\ce{M(CO)5}\]
Identify the metal and justify your answer.
\[\ce{MO3F}\]
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.
Catalytic hydrogenation of benzene gives
Which of the following maxm magnetic moment?
Why is the `"E"_(("V"^(3+)//"V"^(2+)))^"o"` value for vanadium comparatively low?
Give reason for the following statement:
Physical and chemical properties of the 4d and 5d series of the transition elements are quite similar to expected.
How is the variability in oxidation states of transition metals different from that of p-block elements?
Account for the following:
Sc3+ is colourless whereas Ti3+ is coloured in an aqueous solution.
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.
