Amount of oxalic acid present in a solution can be determined by its titration with KMnO4 solution in the presence of H2SO4. The titration gives unsatisfactory result when carried out in the presence of HCl, because HCl

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Amount of oxalic acid present in a solution can be determined by its titration with KMnO4 solution in the presence of H2SO4. The titration gives unsatisfactory result when carried out in the presence of HCl, because HCl

(1) gets oxidised by oxalic acid to chlorine
(2) furnishes H+ ions in addition to those from oxalic acid
(3) reduces permanganate to Mn2+
(4) oxidises oxalic acid to carbon dioxide and water

Anonymous User tag : Chemistry 18 Nov, 2020 1 Answer 56 views

At 80 C, the vapour pressure of pure liquid ‘A’ is 520 mm Hg and that of pure liquid ‘B’ is 1000 mm Hg. If a mixture solution of ‘A’ and ‘B’ boils at 80 C and 1 atm pressure, the amount of ‘A’ in the mixture is (1 atm = 760 mm Hg)

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At 80 C, the vapour pressure of pure liquid ‘A’ is 520 mm Hg and that of pure liquid ‘B’ is 1000 mm
Hg. If a mixture solution of ‘A’ and ‘B’ boils at 80 C and 1 atm pressure, the amount of ‘A’ in the mixture is (1 atm = 760 mm Hg)

Anonymous User tag : Chemistry 18 Nov, 2020 1 Answer 55 views




The rate law for a reaction between the substances A and is given by rate = k [A]n[B]m. On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as :

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The rate law for a reaction between the substances A and is given by rate = k [A]n[B]m. On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as :

Anonymous User tag : Chemistry 01 Nov, 2020 1 Answer 53 views



If at 298K the bond energies of C--H, C-C, C = C, and H-H bonds are respectively 414, 347, 615, and 435 kJ  mol-1. The value of enthalpy change for the reaction

H2C = CH2(g) + H2(g) -->H3C - CH33(g) at 298K will be:

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If at 298K the bond energies of C--H, C-C, C = C, and H-H bonds are respectively 414, 347, 615, and 435 kJ  mol-1. The value of enthalpy change for the reaction

H2C = CH2(g) + H2(g) -->H3C - CH33(g) at 298K will be:

Anonymous User tag : Chemistry 01 Nov, 2020 1 Answer 52 views













































A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 37.0° C. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be :
(R = 8.314 J / mol K) (ln 7.5 = 2.01)

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A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 37.0° C. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be :
(R = 8.314 J / mol K) (ln 7.5 = 2.01)

Anonymous User tag : Chemistry 26 Sep, 2020 1 Answer 53 views













Resistance of 0.2 M solution of an electrolyte is 50 Ω. The specific conductance of the solution is 1.4 S m−1. The resistance of 0.5 M solution of the same electrolyte is 280 Ω. The molar conductivity of 0.5 M solution of the electrolyte in S m2 mol−1 is :

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Resistance of 0.2 M solution of an electrolyte is 50 Ω. The specific conductance of the solution is 1.4 S m−1. The resistance of 0.5 M solution of the same electrolyte is 280 Ω. The molar conductivity of 0.5 M solution of the electrolyte in S m2 mol−1 is :

Anonymous User tag : Chemistry 23 Sep, 2020 1 Answer 53 views


For the estimation of nitrogen, 1.4 g of an organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in 60 mL of M/10 sulphuric acid. The unreacted acid  required 20 mL of M/10 sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is :

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For the estimation of nitrogen, 1.4 g of an organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in 60 mL of M/10 sulphuric acid. The unreacted acid  required 20 mL of M/10 sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is :

Anonymous User tag : Chemistry 23 Sep, 2020 1 Answer 52 views









States of matter

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two gases A and B are at same temperature , the molecules of A are travelling 4 times faster than the molecules of B . the ratio of MA/MB of their masses will be

 

Anonymous User tag : Chemistry 20 Sep, 2020 1 Answer 56 views

Bond lenght

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Calculate the bond length of HCl molecule if its moment of inertia is 2×10–40 gm
cm2 and reduced mass is 1.0 g mol–1.

Anonymous User tag : Chemistry 16 Sep, 2020 0 Answer 74 views
















20 g of non-electrolyte, non-volatile solute (CxH2xOx), when dissolved in 100 gm water at 100°C, lowers the vapour pressure of solution by 1/100 th of the vapour pressure of pure water at this temperature. What is formula of the compound?

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20 g of non-electrolyte, non-volatile solute (CxH2xOx), when dissolved in 100 gm water at 100°C, lowers the vapour pressure of solution by 1/100 th of the vapour pressure of pure water at this temperature. What is formula of the compound?

Anonymous User tag : Chemistry Solutions 11 May, 2020 1 Answer 136 views



























 In a crystalline solid, anion B are arranged in cubic close packing and cation A are equally distributed between octahedral and tetrahedral voids. If all the octahedral voids are occupied, the formula for the solid is

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 In a crystalline solid, anion B are arranged in cubic close packing and cation A are equally distributed between octahedral and tetrahedral voids. If all the octahedral voids are occupied, the formula for the solid is

Anonymous User tag : Chemistry Solid State 02 May, 2020 1 Answer 80 views
















For a first order reaction A -> P, the temperature (T) dependent rate constant (k) was found to follow the equation log k = – (2000) 1/T + 6.0. The pre-exponential factor A and the activation energy Ea, respectively, are

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For a first order reaction A -> P, the temperature (T) dependent rate constant (k) was found to follow the equation
log k = – (2000) 1/T + 6.0. The pre-exponential factor A and the activation energy Ea, respectively, are

Anonymous User tag : Chemistry Chemical Kinetics 01 May, 2020 1 Answer 65 views



Consider a reaction aG + bH -> Products. When concentration of both the reactants G and H is doubled, the rate increases by eight times. However, when concentration of G is doubled keeping the concentration of H fixed, the rate is doubled. The overall order of the reaction is

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Consider a reaction aG + bH -> Products. When concentration of both the reactants G and H is doubled, the rate increases by eight times. However, when concentration of G is doubled keeping the concentration of H fixed, the rate is doubled. The overall order of the reaction is

Anonymous User tag : Chemistry Chemical Kinetics 01 May, 2020 1 Answer 61 views






A decapeptide (Mol. Wt. 796) on complete hydrolysis gives glycine (Mol. Wt. 75), alanine and phenylalanine. Glycine contributes 47.0% to the total weight of the hydrolysed products. The number of glycine units present in the decapeptide is?

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A decapeptide (Mol. Wt. 796) on complete hydrolysis gives glycine (Mol. Wt. 75), alanine and phenylalanine. Glycine contributes 47.0% to the total weight of the hydrolysed products. The number of glycine units present in the decapeptide is?

Anonymous User tag : Chemistry Biomolecules 30 Apr, 2020 1 Answer 66 views














A hydrocarbon (A) adds one mole of hydrogen in the presence of platinum gives hexane. When (A) was oxidised with KMnO4 it gave a single carboxylic acid, containing three carbon atoms. Give the structure and name of (A)

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A hydrocarbon (A) adds one mole of hydrogen in the presence of platinum gives hexane. When (A) was oxidised with KMnO4 it gave a single carboxylic acid, containing three carbon atoms. Give the structure and name of (A)

Anonymous User tag : Chemistry Hydrocarbons 29 Apr, 2020 1 Answer 64 views

896 ml vapour of a hydrocarbon ‘A’ having carbon 87.80% and hydrogen 12.19% weighs 3.28 g at STP. Hydrogenation of ‘A’ gives 2-methyl pentane. Also the hydration of hydrocarbon ‘A’ gives compound ‘B’. Compound ‘B’ gives yellow precipitate with sodium hypoiodite. Find the structure of A and give the reactions involved.

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896 ml vapour of a hydrocarbon ‘A’ having carbon 87.80% and hydrogen 12.19% weighs 3.28 g at STP. Hydrogenation of ‘A’ gives 2-methyl pentane. Also the hydration of hydrocarbon ‘A’ gives compound ‘B’. Compound ‘B’ gives yellow precipitate with sodium hypoiodite. Find the structure of A and give the reactions involved.

Anonymous User tag : Chemistry Hydrocarbons 29 Apr, 2020 1 Answer 69 views






















A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dil. HNO3. The anion could be

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A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dil. HNO3. The anion could be

Anonymous User tag : Chemistry 23 Apr, 2020 1 Answer 60 views

Given the molecular formula of the hexa-coordinated complexes (i) CoCl3.6NH3, (ii) CoCl3.5NH3, (iii) CoCl3.4NH3 If the number of co-ordinated NH3 molecules in (i), (ii) and (iii) respectively are 6, 5, 4, the primary valencies in (i), (ii) and (iii) are :

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Given the molecular formula of the hexa-coordinated complexes (i) CoCl3.6NH3, (ii) CoCl3.5NH3, (iii) CoCl3.4NH3 If the number of co-ordinated NH3 molecules in (i), (ii) and (iii) respectively are 6, 5, 4, the primary valencies in (i), (ii) and (iii) are :

Anonymous User tag : Chemistry 23 Apr, 2020 1 Answer 67 views









A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dil. HNO3. The anion could be

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A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the solution, a white precipitate is obtained which does not dissolve in dil. HNO3. The anion could be

Anonymous User tag : Chemistry 22 Apr, 2020 1 Answer 63 views

Given the molecular formula of the hexa-coordinated complexes (i) CoCl3.6NH3, (ii) CoCl3.5NH3, (iii) CoCl3.4NH3 If the number of co-ordinated NH3 molecules in (i), (ii) and (iii) respectively are 6, 5, 4, the primary valencies in (i), (ii) and (iii) are :

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Given the molecular formula of the hexa-coordinated complexes (i) CoCl3.6NH3, (ii) CoCl3.5NH3, (iii) CoCl3.4NH3 If the number of co-ordinated NH3 molecules in (i), (ii) and (iii) respectively are 6, 5, 4, the primary valencies in (i), (ii) and (iii) are :

Anonymous User tag : Chemistry 22 Apr, 2020 1 Answer 73 views