A to Z Exams

A mixture of Boran trichloride and hydrogen is subjected to silent electric discharge to form ’A’ and HCl. ’A’ is mixed with NH3 and heated to 2000 C to form B. The formula of B is

Which one of the following statements is correct

The rate equation for the reaction A+2B→products is rate=K[A][B]2. If the volume of the vessel is decreased to half of the initial volume the reaction rate bears the following relation to the original rate

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

The difference in ΔH and ΔE for the combustion of methane at 270C would be

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

In the Dewar's method of separation of noble gases, the mixture of noble gases is kept in contact with coconut charcoal at 173K. Which one of the following gaseous mixtures is not adsorbed on to the charcoal ?

The oxidation state of Mo in MO2 (Cl8)4- ion is

The molarity of pure water is:

The chemical formula of 'tear gas is :

Which of the following is a favourable factor for cation formation

Which of the following reacts with ammoniacal cuprous chloride

If H++OH-→H2O.ΔH=-57.3 KJ, then the heat of neutralization for complete neutralization of 1 mole H2SO4 by a base is

The r.m.s. velocity of an ideal gas at 300 K is 12240 cm/sec. What is the most probable velocity at that temperature?

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

Dipole moment of HC1 = 1.03 D, HI = 0.38 D. Bond length of HC1 = 1.3 and HI = 1.6A .The ratio of fraction of an electric charge, δ, existing on each atom in HC1 and HI is

Chemisorption involves

Which of the following set of variables give a straight line with a negative slope when plotted ?(P - vapour pressure, T = Temperature in K)

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

In 0.01 M solution,HCN is 0.01% ionized. Its dissociation constant is

The chemical entities present in thermosphere of the atmosphere

Which of the following reagents can form a hydrazone with alkanone

Which of the following reacts with ethanol to form chloroform

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.

Which of the following pair of transition metal ions, have the same calculated values of magnetic moment

Which of the following statements is correct

The molecular formula of potash alum 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)

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

Which of the following statements is NOT correct?

The nature of forces operating between the adsorbate and the adsorbent in the adsorption occurring at high temperature 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

A codon has a sequence of A and specifies a particular B that is to be incorporated into aC What areA, B, C

The equilibrium constant for the reactionSO2(g) + (1/2) O2(g) <====> SO3(g) is  5 x 10-2 atm  The equilibrium constant of the reaction2SO3(g)  <====> 2SO2(g) + O2(g) would be

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

28g of N2 and 6g of H2 were mixed initially .At equilibrium 17g of NH3 was formed.The weight of N2 and H2 at equilibrium are respectively

The first organic compound synthesized in the laboratory from an inorganic compound is:

The following is a reversible reaction

'Natalite' is used as

Bond energy of Cl2,Br2 and I2 follow the order

The molar ionic conductivities of NH4+ and OH- at infinite dilution are 72 and 198 ohm-1cm2mol-1 respectively.The molar conductance of a centinormal NH4OH solution at the same temperature is found to be 9 ohm-1cm2mol-1,The percentage dissociation of NH4OH at this concentration will be

90 grams of water and 230 grams of an organic liquid n mixing gives a solution in which the mole fraction of water in the resulting solution is 0.5 the molecular weight of the organic liquid is

Which of the following compounds answer positively carbyl amine test? A) C6H5NHCH3 B) CH3-C6H6-NH2 C) C6H6-NH2 D) C6H6-NH (CH3)2

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

Which of the following compounds when heated with CO at 150"C and 500 atm pressure in presence of BF3 forms ethyl propionate ?

In the Born-Haber cycle of the given reaction Na(s) + (1/2)Cl2(g) →NaCl(s)the number of endothermic and exothermic stages respectively are

x grams of calcium carbonate was completely burnt in air. The weight of the solid residue formed is 28g. What is the value of x (in grams)

Which of the following is a biodegradable polymer

Which one of the following is used in the preparation of styrene?

Which of the following is an example of interstitial hydride

X liter of carbon monoxide is present at STP. It is completely oxidized to CO2. The volume of CO2 formed is 11.207 litres. What is the value of X in litres

Which one of the following compounds liberates CO2 from aqueous NaHCO3

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

At 270C the Kp value for the reaction PCl5(g)⇔PCl3(g)+Cl2(g).is 0.65.Its Kc is

The amount of electricity that can deposit 108gm of silver from AgNO3 solution is

The time for half life of a first order reaction is 1 hour. What is the time taken for 87.5% completion of the reaction

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

The heat of neutralization of strong acid and weak base is

On passing a current through molten KCl 19.5g of K is deposited.The amount of aluminium deposited by the same quantity of electricity if passed through molten AlCl3 is

In the long form of periodic table, the elements having lowest ionisation potential are present in :

Ethylene reacted with bromine in CCl4 to form X. When X is reacted with alcoholic KOH, Y is formed. X and Y are respectively :

Nitro benzene on reduction with zinc and NH4CI gives

In nuclear reactor, heavy water is used as a :

Which one of the following is used as an acid flux in metallurgy ?

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

Increasing the conc. of the reactant by 27 times, the rate increases by 3 times. What is the order of the reaction?

Which of the following is not correct

The Kc for the reaction A+B↔C is 4 and Kc for 2A+D↔C is 6. The value of Kc for C+D↔2B is

The froth floatation process is used for the concentration of

Assertion (A) : A catalyst increases the rate of a reaction.Reason (R) : In presence of a catalyst, the activation energy of the reaction increases. The correct answer is

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

Bhopal gas tragedy of 1984 was caused by

The pH of a solution of H2O2 is 6.0, Some chlorine gas is bubbled into this solution. Which of the following is correct

The hydronium ion concentration of a solution is 1X10-4 M at 250 C.The hydroxide ion concentration in the same solution 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

The half-life period of a radioactive element is 120 days. After 480 days 4.0 gm of the element will be reduced to (.....) gms.

9.2 grams of N2O4(g) is taken one liter vessel and heated till the following equilibrium is reached N2O4 (g)⇔2NO2(g).At equilibrium 50% of N2O4(g) is dissociated.The value of Kc is

One mole of alkene X on ozonolysis gave one mole of acetaldehyde and one mole of acetone. The IUPAC name of X is

The solubility of LiOH in a solution of pH = 8 = is Ksp = 1.8 x 10-12

A moving electron has 4.55 x 10-25 joules of kinetic energy. The wavelength of the electron is (mass = 9.1 x 10-31 kg and h = 6.6 x 10-34 kg m2 sec-1)

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

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

If the length of the unit cell is 5 Ao. the smallest distance in Ao between the two neighbouring metal atoms in a face centred cubic lattice is

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

For the redox reaction Cr2O72+ + C2O42+ + H+ → Cr3+ + CO2 + H2O the correct coefficients of Cr2O72-, C2O42- and H+ in the balanced equation are

The number of pπ - dπ 'pi' bonds present in XeO3and XeO4molecules, respectively are

An isomer of ethanol is

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

Identify the correct decreasing order of the following with respect to altitude from atmosphere:I. Troposphere    II. Mesosphere  III. Thermosphere

A solution of concentration "C" g equiv/litre has a specific resistance R, The equivalent conductance of the solution is

Gold number is used to show

If a solid is dispersed in a liquid the colloid is called

Which of the following pair of ions have same paramagnetic moment

The magnetic oxide of iron is

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

Cuprous ion is colourless while cupric ion is coloured because :

What are the metal ions present in carnallite ?

Among the following compounds which have more than one type of hybridization for carbon atom 1) CH3CH2CH2CH3 2) CH3CH= CHCH3 3) CH2= CH-CH=CH2 4) H-C=C-H

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

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