Advertisements
Advertisements
प्रश्न
Identify A to E and also explain the reactions involved.
Advertisements
उत्तर
A = \[\ce{Cu}\]
B = \[\ce{Cu(NO3)2}\]
C = \[\ce{[Cu(NH3)4]}\]
D = \[\ce{CO2}\]
E = \[\ce{CaCO3}\]
F = \[\ce{Cu2[Fe(CN)6]}\]
G = \[\ce{Ca (HCO3)2}\]
\[\ce{CuCO3 -> CuO + CO2}\]
\[\ce{CuO + CuS -> \underset{(A)}{Cu} + SO2}\]
\[\ce{Cu + 4HNO3 (Conc) -> Cu \underset{(B)}{(NO3)2} + 2NO + 2H2O}\]
\[\ce{\underset{(B)}{Cu^2+} + NH3 -> \underset{(C)}{[Cu(NH3)4]}}\]
\[\ce{Ca(OH)2 + \underset{(D)}{CO2} -> \underset{(E)}{CaCO3} + H2O}\]
\[\ce{CaCO3 + CO2 + H2O -> Ca(HCO3)2}\]
APPEARS IN
संबंधित प्रश्न
Why do interstitial compounds have higher melting points than corresponding pure metals?
|
`E_((M^(2+)/M)` |
Cr | Mn | Fe | Co | Ni | Cu |
| -0.91 | -1.18 | -0.44 | -0.28 | -0.25 | -0.34 |
From the given data of E0 values, answer the following questions :
(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive
(2) Why is `E_(((Mn^(2+))/(Mn)))` value is highly negative as compared to other elements
(3) Which is the stronger reducing agents Cr2+ or Fe2+ ? Give Reason.
How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?
Predict which of the following will be coloured in the aqueous solution?
Ti3+, V3+, Cu+, Sc3+, Mn2+, Fe3+ and Co2+. Give reasons for each.
How would you account for the following:
Of the d4 species, Cr2+ is strongly reducing while manganese (III) is strongly oxidising.
How would you account for the following:
The d1 configuration is very unstable in ions.
What are inner transition elements?
Use Hund’s rule to derive the electronic configuration of Ce3+ ion and calculate its magnetic moment on the basis of ‘spin-only’ formula.
How would you account for the following?
Transition metals and their compounds act as catalysts.
How is potassium dichromate prepared from chrome iron ore?
Transition metals with lowest melting point is ______.
Maximum magnetic moment is shown by ____________.
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.
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.
Assertion (A): Cu cannot liberate hydrogen from acids.
Reason (R): Because it has positive electrode potential.
Fill in the blanks by choosing the appropriate word(s) from those given in the brackets:
(activation energy, Threshold energy, increased, lowered, partially, full, d-d transition, Benzoic acid, benzaldehyde)
Only those transition metal ions will be coloured which have ______ filled d-orbitals facilitating ______.
Consider the following standard electrode potential values:
\[\ce{Sn^{2+}_{ (aq)} + 2e^- -> Sn_{(s)}}\]; E0 = −0.14 V
\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\]; E0 = +0.77 V
What is the cell reaction and potential for the spontaneous reaction that occurs?
Write the number of unpaired electrons in Cr3+.
(Atomic number of Cr = 24)
