Class 12th Chemistry 2017 Set1 Delhi Board Paper Solution
Out of Cu+ and Cu2+, which ion is unstable in aqueous solution and why?
Cu+ is unstable in aqueous solution than Cu2+ because although 2nd I.E. of copper is large but hydration enthalpy for Cu2+ is much more negative than that for Cu+ and hence, it is more than compensates for the 2nd I.E. of copper. Therefore, many Cu+ compounds are unstable in aqueous solution and undergo disproportionation.
2Cu+ → Cu2+ + Cu
Popular Questions of Class 12th chemistry
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How the following conversions can be carried out?
(i) Propene to propan-1-ol
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(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide
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Give simple chemical tests to distinguish between the following pairs of compounds.
(i) Propanal and Propanone
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(v) Pentan-2-one and Pentan-3-one
(vi) Benzaldehyde and Acetophenone
(vii) Ethanal and Propanal
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A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.
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Calculate the mole fraction of benzene in solution containing 30% by mass in carbon tetrachloride.
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If NaCl is doped with 10-3mol % of SrCl2, what is the concentration of cation vacancies?
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