Class 12th Chemistry 2017 Set3 Outside Delhi Board Paper Solution
Give reasons for the following:
(a) Red phosphorus is less reactive than white phosphorus .
(b) Electron gain enthalpies of helogens are largely negative.
(c) N2O5 is more acidic than N2O3.
(a) Red phosphorus is less reactive then white phosphorus because it is more stable due to its polymeric structure.
(b) The Electron gain enthalpy of halogens is highly negative because it needs only one electron to achieve nearest noble gas configuration.
(c) N2O5 is more acidic because it form HNO3 with H2O and while N2O3 forms HNO2 with H2O.
Popular Questions of Class 12th chemistry
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Give simple chemical tests to distinguish between the following pairs of compounds.
(i) Propanal and Propanone
(ii) Acetophenone and Benzophenone
(iii) Phenol and Benzoic acid
(iv) Benzoic acid and Ethyl benzoate
(v) Pentan-2-one and Pentan-3-one
(vi) Benzaldehyde and Acetophenone
(vii) Ethanal and Propanal
- Q:-
How the following conversions can be carried out?
(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(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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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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A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If the density of solution is 1.2 g mL-1, then what shall be the molarity of the solution?
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Henry's law constant for CO2 in water is 1.67 x 108Pa at 298 K. Calculate the quantity of CO2in 500 mL of soda water when packed under 2.5 atm CO2 pressure at 298 K.
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Calculate the mass of a non-volatile solute (molar mass 40 g mol-1) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.
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The vapour pressure of pure liquids A and B are 450 and 700 mm Hg respectively, at 350 K. Find out the composition of the liquid mixture if total vapour pressure is 600 mm Hg. Also find the composition of the vapour phase.
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Calculate the mole fraction of benzene in solution containing 30% by mass in carbon tetrachloride.
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How many mL of 0.1 M HCl are required to react completely with 1 g mixture of Na2CO3 and NaHCO3 containing equimolar amounts of both?
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If NaCl is doped with 10-3mol % of SrCl2, what is the concentration of cation vacancies?
Recently Viewed Questions of Class 12th chemistry
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While antacids and anti allergic drugs interfere with the function of histamines, why do these not interfere with the function of each other ?
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Give the IUPAC names of the following compounds:
(i) PhCH2CH2COOH (ii) (CH3)2C=CHCOOH
(iii)
(iv) 
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Why is the ester hydrolysis slow in the beginning and becomes faster after sometime?
- Q:-
From the rate expression for the following reactions, determine their order of reaction and the dimensions of the rate constants.
(i) 3 NO(g) → N2O(g) Rate = k[NO]2
(ii) H2O2 (aq) + 3 I - (aq) + 2 H+→ 2 H2O (l) + I3- Rate = k[H2O2][I - ]
(iii) CH3CHO(g) → CH4(g) + CO(g) Rate = k [CH3CHO]3/2
(iv) C2H5Cl(g) → C2H4(g) + HCl(g) Rate = k [C2H5Cl]
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Among the isomeric alkanes of molecular formula C5H12, identify the one that on photochemical chlorination yields
(i) A single monochloride.
(ii) Three isomeric monochlorides.
(iii) Four isomeric monochlorides.
- Q:-
The following data were obtained during the first order thermal decomposition of SO2Cl2at a constant volume.
SO2Cl2(g) → SO2(g) + Cl2(g)
Experiment Time/s - 1
Total pressure/atm 1 0 0.5 2 100 0.6 Calculate the rate of the reaction when total pressure is 0.65 atm.
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Why is it essential to wash the precipitate with water before estimating it quantitatively?
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How is SO2 an air pollutant?
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Explain why inspite of nearly the same electronegativity, oxygen forms hydrogen bonding while chlorine does not.
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Which is the last element in the series of the actinoids? Write the electronic configuration of this element. Comment on the possible oxidation state of this element.