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 106 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 60 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 62 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 58 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 61 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 60 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 63 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 56 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 62 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 58 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 60 views








Two liquids X and Y form an ideal solution. At 300 K, vapour pressure of the solution containing 1mol of X and 3 mol of Y is 550 mm Hg.Atthesame temperature, if 1 mol of Y is further added to this solution, vapour pressure of the solution increases by 10 mm Hg. Vapour pressure (in mm Hg) of X and Y in their pure states will be, respectively

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Two liquids X and Y form an ideal solution. At 300 K, vapour pressure of the solution containing 1mol of X and 3 mol of Y is 550 mm Hg.Atthesame temperature, if 1 mol of Y is further added to this solution, vapour pressure of the solution increases by 10 mm Hg. Vapour pressure (in mm Hg) of X and Y in their pure states will be, respectively

Anonymous User tag : Chemistry Solutions 20 Apr, 2020 1 Answer 61 views









A radioactive element gets spilled over the floor of  a room. Its half­life period is 30 days. If the initial velocity is ten times the permissible value, after how many days will it be safe to enter the room?

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A radioactive element gets spilled over the floor of  a room. Its half­life period is 30 days. If the initial velocity is ten times the permissible value, after how many days will it be safe to enter the room?

Anonymous User tag : Chemistry Nuclear Chemistry 19 Apr, 2020 1 Answer 58 views


























The behaviour of a real gas is usually depicted by plotting compressibility factor Z versus P at a constant temperature. At high temperature and high pressure, Z is usually more than one. This fact can be explained by van der Waals equation when

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The behaviour of a real gas is usually depicted by plotting compressibility factor Z versus P at a constant temperature. At high temperature and high pressure, Z is usually more than one. This fact can be explained by van der Waals equation when

Anonymous User tag : Chemistry 09 Apr, 2020 1 Answer 58 views








Salts of A (atomic weight 7), B (atomic weight = 27) and C (atomic weight 48) were electrolysed under identical conditions using same quantity of electricity. It was found that when 2.1g of A was deposited, weights of B and C deposited were 2.7g and 7.2g. The valencies of A, B and C are respectively.

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Salts of A (atomic weight 7), B (atomic weight = 27) and C (atomic weight 48) were electrolysed under identical conditions using same quantity of electricity. It was found that when 2.1g of A was deposited, weights of B and C deposited were 2.7g and 7.2g. The valencies of A, B and C are respectively.

Anonymous User tag : Chemistry 07 Apr, 2020 1 Answer 58 views


At 88°C benzene has a vapour pressure of 900 torr and toluene has a vapour pressure of 360 torr. What is the mole fraction of benzene in mixture with toluene that will boil at 88°C at 1 atm pressure assuming ideal solution.

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At 88°C benzene has a vapour pressure of 900 torr and toluene has a vapour pressure of 360 torr. What is the mole fraction of benzene in mixture with toluene that will boil at 88°C at 1 atm pressure assuming ideal solution.

Anonymous User tag : Chemistry 07 Apr, 2020 1 Answer 85 views

The ionisation energy of solid NaCl is 180 kcal/mol. The dissolution of the solid in water is endothermic to the extent of 1 kcal per mol. If the solvation energies of Na+ and Cl– ions are in the ratio 6:5, what is the enthalpy of hydration of sodium ion

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The ionisation energy of solid NaCl is 180 kcal/mol. The dissolution of the solid in water is endothermic to the extent of 1 kcal per mol. If the solvation energies of Na+ and Cl– ions are in the ratio 6:5, what is the enthalpy of hydration of sodium ion

Anonymous User tag : Chemistry 07 Apr, 2020 1 Answer 55 views










2 g of a gas A is introduced into an evacuated flask kept at 25°C. The pressure is found to be 1 atm. If 3 g of another gas B is added to the same flask the total pressure becomes 1.5 atm, assuming ideal gas behaviour. The ratio of molecular weight of gas A to gas B (MA : MB) is

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2 g of a gas A is introduced into an evacuated flask kept at 25°C. The pressure is found to be 1 atm. If 3 g of another gas B is added to the same flask the total pressure becomes 1.5 atm, assuming ideal gas behaviour. The ratio of molecular weight of gas A to gas B (MA : MB) is

Anonymous User tag : Chemistry State of matter 05 Apr, 2020 1 Answer 54 views

50 ml of mixture of NH3 and H2 are decomposed to yield N2 and H2 and to the resulting mixture 40 ml O2 is added and the mixture is sparked to yield H2O. When the resulting mixture of gases were passed through alkaline pyrogallol 6 ml contraction was observed. Calculate the percentage composition of NH3 in the original mixture

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50 ml of mixture of NH3 and H2 are decomposed to yield N2 and H2 and to the resulting mixture 40 ml O2 is added and the mixture is sparked to yield H2O. When the resulting mixture of gases were passed through alkaline pyrogallol 6 ml contraction was observed. Calculate the percentage composition of NH3 in the original mixture

Anonymous User tag : Chemistry State of matter 05 Apr, 2020 1 Answer 79 views

A 10 cm air column is trapped inside the tube (having uniform area of cross section) by 6 cm of Hg and is placed horizontally to the plane. Calculate the length of air column when the tube is placed vertically with opened end up.

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A 10 cm air column is trapped inside the tube (having uniform area of cross section) by 6 cm of Hg and is placed horizontally to the plane. Calculate the length of air column when the tube is placed vertically with opened end up.

Anonymous User tag : Chemistry State of matter 05 Apr, 2020 1 Answer 65 views

A vertical hollow cylinder of height 152 cm is fitted with a weightless piston. The lower half is filled with an ideal gas and the upper half with mercury.The cylinder is now heated at300K,so that 1/4th of the mercury comes out.Find the temperature at which it will happen assuming thermal expansion of Hg to be negligible

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A vertical hollow cylinder of height 152 cm is fitted with a weightless piston. The lower half is filled with an ideal gas and the upper half with mercury.The cylinder is now heated at300K,so that 1/4th of the mercury comes out.Find the temperature at which it will happen assuming thermal expansion of Hg to be negligible

Anonymous User tag : Chemistry State of matter 05 Apr, 2020 1 Answer 54 views





1 mole of gas H2 and 4 moles of gas O2 is taken inside the vessel, which effuse through a small orifice of the vessel having same area of cross section and at the same temperature, then which is the correct % of effused volume of gas H2 and O2 initially respectively? (Assume that the gas H2 does not react with O2 gas)

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1 mole of gas H2 and 4 moles of gas O2 is taken inside the vessel, which effuse through a small orifice of the vessel having same area of cross section and at the same temperature, then which is the correct % of effused volume of gas H2 and O2 initially respectively? (Assume that the gas H2 does not react with O2 gas)

Anonymous User tag : Chemistry State of matter 05 Apr, 2020 1 Answer 68 views





Explain the following a) Although Au is soluble in aqua-regia, Ag is not b) Zinc and hot copper is used for recovery of Ag from the complex [Ag(CN)2]– c) Aluminium metal is frequently used as a reducing agent for extraction of metal such as chromium manganese etc. d) Partial roasting of sulphide ore is done in the metallurgy of copper.

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Explain the following
a) Although Au is soluble in aqua-regia, Ag is not
b) Zinc and hot copper is used for recovery of Ag from the complex [Ag(CN)2]–

c) Aluminium metal is frequently used as a reducing agent for extraction of metal such as chromium manganese etc.

d) Partial roasting of sulphide ore is done in the metallurgy of copper.

Anonymous User tag : Chemistry Matallurgy 31 Mar, 2020 1 Answer 65 views






Solubility product of silver bromide is 5.0 × 10–13. The quantity of potassium bromide (molar mass taken as 120 g mol–1) to be added to 1 litre of 0.05 M solution of silver nitrate to start the precipitation of AgBr is

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Solubility product of silver bromide is 5.0 × 10–13. The quantity of potassium bromide (molar mass taken as 120 g mol–1) to be added to 1 litre of 0.05 M solution of silver nitrate to start the precipitation of AgBr is

Anonymous User tag : Chemistry Equilibrium 29 Mar, 2020 1 Answer 66 views



29.5 mg of an organic compound containing nitrogen was digested according to Kjeldahl's method and the evolved ammonia was absorbed in 20 mL of 0.1 M HCl solution. The excess of the acid required 15 mL of 0.1 M NaOH solution for complete neutralisation. The percentage of nitrogen in the compound is?

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29.5 mg of an organic compound containing nitrogen was digested according to Kjeldahl's method and the evolved ammonia was absorbed in 20 mL of 0.1 M HCl solution. The excess of the acid required 15 mL of 0.1 M NaOH solution for complete neutralisation. The percentage of nitrogen in the compound is?

Anonymous User tag : Chemistry 29 Mar, 2020 1 Answer 57 views







In a multi­electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields? (i)  n=1,l=0,m=0 (ii)  n=2,l=0,m=0 (iii)  n=2,l=1,m=1 (iv)  n=3,l=2,m=1 (v)  n=3,l=2,m=0

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In a multi­electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic and electric fields?

(i)  n=1,l=0,m=0

(ii)  n=2,l=0,m=0

(iii)  n=2,l=1,m=1

(iv)  n=3,l=2,m=1

(v)  n=3,l=2,m=0

Anonymous User tag : Chemistry Structure of Atom 24 Mar, 2020 1 Answer 53 views














































Benzene and toluene form nearly ideal solutions. At 20°C, the vapour pressure of benzene is 75 torr and that of toluene is 22 torr. The partial vapour pressure of benzene at 20°C for a solution containing 78 g of benzene and 46 g of toluene in torr is

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Benzene and toluene form nearly ideal solutions. At 20°C, the vapour pressure of benzene is 75 torr and that of toluene is 22 torr. The partial vapour pressure of benzene at 20°C for a solution containing 78 g of benzene and 46 g of toluene in torr is

Anonymous User tag : Chemistry Solutions 15 Mar, 2020 1 Answer 52 views




An organic liquid with sweet smell and b.pt 78°C contains C, H and O. On heating with conc. H2SO4 gives a gaseous product (B) of empirical formula (CH2)n. Compound (B) decolourises bromine water and alk. KMnO4. (B) also reacts with one mole of H2 in presence of Ni. What are (A) and (B)?

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An organic liquid with sweet smell and b.pt 78°C contains C, H and O. On heating with conc. H2SO4 gives a gaseous product (B) of empirical formula (CH2)n. Compound (B) decolourises bromine water and alk. KMnO4. (B) also reacts with one mole of H2 in presence of Ni. What are (A) and (B)?

Anonymous User tag : Chemistry Alcohols Phenols and Ethers 15 Mar, 2020 0 Answer 53 views


Although both polymers are prepared by free radical processes, poly (vinyl chloride) is amorphous and poly (vinylidene chloride) (saran) is highly crystallilne. How do you account for the different? (vinylidene chloride is 1,1- dichloroethene).

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Although both polymers are prepared by free radical processes, poly (vinyl chloride) is amorphous and poly (vinylidene chloride) (saran) is highly crystallilne. How do you account for the different? (vinylidene chloride is 1,1- dichloroethene).

Anonymous User tag : Chemistry Polymers 15 Mar, 2020 1 Answer 53 views