A to Z Exams

The wavelengths of electron waves in two orbits is 3 : 5. The ratio of kinetic energy of electrons will be

Consider the following reaction N2 (g)+3H2 (g)⇔2NH3 (g).Initially ,1 mole of N2 and 3 moles of H2 are taken in a 2 litre flask.At equilibrium state if the number of moles of N2 is 0.6 what is the total number moles of all gases present in the flask at equilibrium

Method used for the concentration of tinstone ore is

SiCl4 on hydrolysis forms X and HCI. Compound X loses water at 1000oC and gives Y. Compounds X and Y respectively are

The weakest acid among the following is

The molar capacity(Cp)of water at constant pressure is 75 J.K-1.mol-1.The increase in temperature (in K) of 100 g of water when 1 K.J. of heat is supplied to it is

An endothermic reaction A→B has an activation energy 15 kCal/mole and energy of the reaction is 5 kCal/mole. The activation energy of the reaction B→A is

The final product formed on the strong heating of H3BO3

Given the bond energies of N = N, H — H and N—H bonds as 945, 436 and 391 kj/mol respectively, the enthalpy    of    the    reaction N2(S) + 3H2 (g) —> 2NH3(g) is :

At 270C, 500 mL of helium diffuses in 30 minutes. What is the time (in hours) taken for 1000 mL of SO2 to diffuse under same experimental conditions ?

A mixture of Haematite,coke and limestone on heating in blast furnace gives molten iron metal.This is known as

Which of the following not obtained when methyl chloride and n-propyl chloride react with sodium in dry ether

Assertion (A): The PH of a buffer solution containing equal moles of acetic acid and sodium acetate is 4.8  (pKa of acetic acid is 4.8)Reason (R): The ionic product of water at  250C is l0-14 mol2 .L-2. The correct answer is

The heat of neutralization of strong acid and weak base is

In Fischer-Ringe's method of separation of nobles gas mixture, from air is used

pH of a buffer solution decreases by 0.02 units when 0.12 g of acetic acid is added to 250 ml of a buffer solution of acetic acid and Potassium acetate at 270C. The buffer capacity of the solution is

Which of the following is not correct regarding the properties of ionic compounds ?

x grams of water is mixed in 69 g of ethanol. Mole fraction of ethanol in the resultant solution is 0.6. What is the value of x in grams ?

A(g)+2B(g)⇔2C(g)+D(g) was studied using an initial concentration of B which was 1.5 times that of A .But the equilibrium concentrations of A and B were found to be equal .Then Kc for the equilibrium

Which of the following has S---S bond ?

For the reaction H2(g)+I2(g)⇔2HI(g) at 721 K,the value of equilibrium constant KC is 50.The value of KP under the same conditions will be

The charge required to reduce 1 mole Cr2O7-2 to Cr+3 ions is

A mixture contains 10 g of oxygen, 28g of nitrogen and 8g of CH4.Total pressure of mixture is 740mm.What is the partial pressure of nitrogen in mm

In which of the following reactions, the concentration of reactant is equal to concentration of product at equilibrium(K=equilibrium constant)

9.2 gm of N2O4(g) is taken in a closed one litre vesseland heated till the following equilibrium is reached N2O4(g)⇔2NO2(g).At equilibrium 50% of N2O4(g) is dissociated.what is the equilibrium constant(in mole lit-1)(M.wt of N2O4 is 92)

The number of oxygen atoms bonded to one phosphorus atom in P4O6 is:

The equilibrium constant for the reaction H2(g)+I2(g)⇔2HI(g) is 81 at a certain temperature.If the concentrations of H2 and I2 are 3mole.lit each at equilibrium,the equilibrium concentration of HI is

One mole of A and 2 moles of B are allowed to react in a one lit flask. What is the value of Kc if at equilibrium,0.4 moles of C is formed in the reaction A+2B⇔C+2D

The cell reaction of a cell is Mg(g)+Cu2+(aq)→Cu(g)+Mg2+(aq).If the standard reduction potentials of magnesium and copper are -0.33 and +2.38V respectively,the e.m.f of the cell is:

Equivalent conductance at infinite dilution,λ0 of NH4Cl,NaOH and NaCl are 128.0,217.8 and 109.9 ohm-1cm2eq-1 respectively. The equivalent conductance of 0.01N NH4OH is 9.30 ohm-1cm2eq-1,then the degree of ionization of NH4OH at this temperature would be(approximately)

Vicinal dihalide (C2H4Br2) on heating with excess alc.KOH and Zinc dust gives ’y’ and ‘z’ respectively. Both ‘y’ and ’z’ on oxidation with Bayer’s regent gives A and B.A and B respectively are

The correct structure of 4-bromo 3-methyl-but-1-ene:

The wavelength of a spectral line emitted by hydrogen atom in the Lyman series is (16/15)hr cm  .What is the value of n2   (R= Rydberg Constant)

3-hydroxybutanal is formed when (X) reacts with (Y) in dilute (Z) solution. Whatare X, Y and Z

The formula of the product formed, when sodium thiosulphate solution is added to silver bromide is

For a given reaction which one is higher than the rest among the following

The chemical formula of feldspar is

Which of the following functional group shows +R effect

Which of the following statements is correct

Solubility product of Ba(OH)2 and Al(OH)3 are 1.8x10-10 and 2.4x10-20 respectively.If both Al3+ and Ba+2 ions are present is a solution,which one will be precipated on addition of Ammonium hydroxide solution

Assertion (A) : K, Rb and Cs form superoxides.Reason (R) ;     The stability of the superoxides increase from 'K' to 'Cs' dueto decrease in lattice energy. The correct answer is

For the reaction A(g)⇔B(g)+C(g),Kp at 4000C is 1.5x10-4 and Kp at 6000C is 6x10-3 Then the incorrect statement is

Which of the following has the highest first IP

In aqueous solutions H2O2 oxidises H2S to

which of the following is not correcr?

At 270C the ratio of root mean square velocities of ozone to oxygen is :

148mg of Ca(OH)2 is required to remove hardness of one lit. of hard water by Clarke’s process. If hardness is due to only calcium bicarbonate, what is the degree of hardness of sample of water?

Oxide of nitrogen which gives reddish brown colour when exposed to air is

The average kinetic energy of one molecule of an ideal gas 270C and 1 atm. pressure is

The rate constant of a first order reaction at 27°C is 10-3 min-1. The temperature coefficient of this reaction is 2. What is the rate constant (in min-1) at 17°C for this reaction ?

CCl3COCH3+Ca(OH)2→X+Y. Here X and Y are

Molar conductivity of a solution 1.26 x 102Ω-1cm2mol-1 ,its molarity is 0.01.its specific conductivity will be

The concentration of oxalic acid is 'x'mol L-1. 40 mL of this solution reacts with 16 mL of 0.05 M acidified KMn04. What is the pH  of 'x' M oxalic acid solution ? (Assume that oxalic acid dissociates completely)

Aluminium reacts with NaOH and forms compound X. If the coordination number of aluminium in X is 6, the correct formula of X

Gold number is used to show

H2-O2 fuel cell is

On adding a little phosphorous to silicon, we get a/an

The type of bonds present in sulphuric anhydride

Hydrolysis of sucrose with dilute aqueous sulphuric acid yields

In the reaction BCl3+PH3→[Cl3B←PH3] the lewis base is

What is the time (in sec) required for depositing all the silver present in 125mL of 1 M AgN03 solution by passing a current of 241.25 A ? (1 F = 96500 coulombs)

The value of Kp for the reaction 2H2S(g)⇔2H2(g)+S2(g) is 1.2 x 10-2 at 10650C.The value of KC for the reaction is

The order of decrease in atomic radii for Be;Na;Mg is

Electrolysis of X gives Y at anode. Vacuum distillation of Y gives H2O2. The number of peroxy (O-O) bonds present in X and Y respectively are :

Nitro benzene on reduction with zinc and NH4CI gives

List-I List-II List-III CH3COONa Alc.KOH Ethylene CHCl2-CHCl2 H2O Acetylene C2H5MgI NaOH+CaO Methane CH3-CH2Cl Zn dust Ethane The correct match is

The ΔG in the process of melting of ice at -150C and 1atm pressure is

The equilibrium constants for the reactions N2(g)+O2(g)⇔2NO(g) and NO(g)+1/2 O2(g) are K1 and K2 respectively .Then the equilibrium constant for the reaction N2(g)+O2(g)⇔2NO2(g) is

Zn(s)+Cu+2(ag)→Cu(s)+Zn+2(ag)Given that ΔfG0 for Cu+2(ag) and Zn+2(ag) are +65.0 K.J.mol-1 and -147.2 K.J.mol-1 respectively then the standard Gibbs energy change for the above reaction is

Ethylene reacts with Br2 in CCl4 to from X. When X is reacted with alcoholic KOH. Y is formed. Here X and Y are

Which one of the following compounds forms a quaternary salt on reacting with excess methyl iodide ?

A system absorbs 10kJ of heat and does 4kJ of work. The internal energy of the system

Which of the following is not a conjugate acid-base pair

Which of the following reagents when heated with ethyl chloride, forms ethylene ?

Which of the following is a linear molecule

Which of the following is not correct

Which one of the following compounds in aqueous solution gives a white precipitate with perichloric acid ?

The electrolytic conductance of 0.01 M solution of acetic acid is 0.000163 Scm-1 at 298k. The % of dissociation of acetic acid at 298K.Given Am0 of acetic acid =390.7 Scm-2/mole at 298K.

For the reversible reaction C2H4 + H2 ⇔ C2H6 the equilibrium constant can be expressed in units of

Which one of the following order is correct for the first ionization energies of the elements

Which of the following is not tetrahedral

Which of the following is the anhydride of HNO3

Resonance in benzene is accompanied by delocalization of π –electrons. Each π electron is attached with

The ratio of radii of first orbits of H, He+ and Li+2 i

A quantity of PCl5(g) was heated in a 10 litre vessel at 2500C PCl5(g) ⇔PCl3(g)+Cl2(g) At equilibrium the vessel contains 0.1 mole of PCl5 0.2 mole of PCl3 and 0.2 mole of Cl2 .The equilibrium constant is

A sample of gas has a volume of 0.2 lit. measured at 1 atm. pressure and 00C. At the same pressure, but at 2730C its volume will become

Aniline when heated with NaNO2 and HCl at 0.50C the product formed is:

How many litres of oxygen (at STP) are required for complete combustion of 39 g of liquid benzene?(Atomic weights: C = 12, O = 16, H = 1)

Order of boiling points

CH3COOH ----LiAlH4--->  AA + CH3COOH ---H3O+ ----->  B + H2OIn the above reactions 'A' and 'B' respectively are

Which of the following is not an air pollutant

A gaseous mixture contains 56g of N2,44g of CO2 and 16g of CH4.The total pressure of th mixture is 720 mm Hg.The partial pressure of CH4 is:

Bauxite is a mineral for the extraction of :

An oxide of an element is a gas and dissolves in water to give an acidic solution. The element belongs to

PH of a solution produced when aqueous solution of PH 6 is mixed with an equal volume of an aqueous solution oh PH is about

The number of π bonds in the product formed by passing acetylene through dil.H2SO4 containing mercuric sulphate is:

A sample of 100ml water required 0.294mg of K2Cr2O7(mol.wt=294)for oxidizing dissolved organic compounds in it. The C.O.D of water sample is

The charge present onn one azide ion in columbs is

Which of the following, compounds is the reactant in Rosenmund's reduction

The salt of phosphorous acid are called