A to Z Exams

When the same amount of zinc is treated with excess of H2SO4 and with excess NaOH, the ratio of the volume of H2 evolved is

Which of the following is an endothermic reaction ?

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

An organic compound X on treatment with pyridinium chloro chromate in dichloromethane gives compound 'Y". Compound Y reacts with I2 and alkali to form triiodomethane. The compound 'X' is

In the hardening stage of plaster of paris, the compound formed 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?

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

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

Sodium is heated in air at 3000C to form X. X absorbs CO2 and forms Na2CO3 and Y. Which of the following is Y

An organic compound X on treatment with pyridium dichromate in dichloromethane gives compound Y.Compound Y reacts with I2 and alkali to form idoform.The compound X is

Which of the following is not correct

The numbers of unit cells present in 5.85mg of NaCl crystal are

Which of the following is not correct

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 ?

Assertion(A): A catalyst has no effect on the state of equilibrium Reason:A catalyst influences the rates of both forward and backward reactions to the same extent

CH2=CH2+HCl→CH3CH2Cl is an example for

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

The order of pH of 0.200 M solutions of NH4NO3, NaNO3 and Na2CO3 is

Calculate the emf of the cell   Cu (s) | Cu2+ (aq) || Ag+ (aq) | Ag (s)  GivenEoCu2+/Cu  = +0.34V ,  EoAg+/Ag  =0.80 V

Identify the reaction for which ΔH ≠ ΔE :

The heat of formation (ΔHf) of H2O(g) is -243 KJ.ΔE of it at temperature T is

Which one of the following functional groups undergoes hydrolysis with alkali to yield an acid group

If in a 100 mL of an aqueous HC1 of pH 1.00, 900 mL of more distilled water is added, the pH of the resultant solution will be :

pH of pure H2O at 250C is

In the reaction AlCl3+Cl-→AlCl4-, AlCl3 is

The chemicals and the reaction conditions required for the preparation of ethane are

The number of sigma and pi bonds in peroxodisulphuric acid are, respectively

What is the correct order of occurrence (% by weight) in air of Ne, Ar and Kr ?

The hydrolysis constant Kh of a salt of NaOH and a weak acid (HX) If the Ka of the acid is Ka=2x10-6

Aqueous solution of an organic compound, 'A' on electrolysis liberates acetylene and CO2 at anode. 'A' is

Chloroethane reacts with Y to form NaCl and Z. One mole of Z reacts with two moles of HI to form water and iodo ethane. Which of the following is Y

A complex compound of CO3+ with molecular formula COClx. yNH3 gives a total of 3 ions when dissolved in water. How many Cl- ions satisfy both primary and secondary valencies in this complex

Which of the following is the anhydride of HNO3

Which of the following statements is correct

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 ?

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

The IUPAC name of an unsymmetrical ether with the molecular formula C4H10O:

Number of coulombs of current required to convert completely 1 mole of MnO4- ions in acid medium to one mole of Mn2+ ions electrolytically is

Anhydrous Magnesium chloride can be prepared by heating MgCl2.2H2O

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

 Fluorine reacts with dilute NaOH and forms a gaseous product A. The bond angle in the molecule of A is

What are the metal ions present in carnallite ?

When a sample of gas expands from 4.0L to 12.0L against a constant pressure of 0.30 atm, the work involved is (1L ATM=101.35 J)

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

A sample of water contains 11.1 ppm of CaCl2 and 9.5 ppm of MGCl2 the hardness of water sample is

The molecule having zero dipole moment is:

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

The charge present onn one azide ion in columbs is

The value of Kp for the reaction 2H2S(g) ⇔ 2H2(g) + S2(g) is 1.2X10-2 at 10650C.The value of KC for the reaction

Which one of the following pairs of reactants does not form oxygen when theyreact with each other

Three faradays of electricity are passed through molten Al2O3, aqueous solution of CuSO4 and molten NaCl taken in three different electrolytic cells. The amount of Al,Cu and Na deposited at the cathodes will be in the ratio of

The rate of the reaction at 400C is 5 units.The rate of same reaction at 800C is nearly(temperature coefficient)

consider the following reaction equilibrium 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

Carbogen to

What is the temperature at which the kinetic energy of 0.3 moles of Helium is equal to the kinetic energy of 0.4 moles of Argon at 400 K ?

The half-lives of two radioactive nuclides A and B are 1 and 2 min respectively. Equal weights of A and B are taken separately and allowed to disintegrate for 4 min. What will be the ratio of weights of A and B disintegrated

In the extraction of iron from haematite,the charge used is haematite,coke and lime stone in the following weight ratio

Which of the following halide does not contain a lone pair of electrons on the central atom

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 oxidation states of nitrogen in NH4NO3 is /are

Dry distillation of calcium acetate and calcium formate forms:

If ΔE is the heat of reaction for C2H5OH(1)+3O2(g)→2CO2(g)+3H2O(l) at constant volume,the ΔH(Heat of reaction at constant pressure)at constant temperature is

In the reaction AlCl3+Cl-→[AlCl4]-,AlCl3 acts as

An isomer of ethanol is

Observe the following statements :I.   Bleaching   powder   is   used   in   the preparation of chloroform.II.  Bleaching powder decomposes in the presence ofCoCl2 to liberate 02.III.Aqueous KHF2 is used in the preparation of fluorine.The correct combination is :

For a reversible reaction, if the concentrations of the reactants are doubled, then the equilibrium constant value

Which of the following reagents can form a hydrazone with alkanone

Conjugate base of H2SO4 is

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

The salt of phosphorous acid are called

Three faradays of electricity was passed through an aqueous solution of iron(II) bromide.The weight of iron metal(at.wt=56) deposited at the cathode is(in grams):

The vant Hoff factor for 0.1M Barium nitrate is 2.74. The percentage of dissociation of barium nitrate 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

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 chemical entities present in thermosphere of the atmosphere

An organic compound containing C and H has 92.3% of carbon, Its empirical formula is:

Which of the following statements is NOT correct?

The number of structural alcoholic isomers for C4H10O 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

Average C-H bond energy is 416 kJ. mol-1. Which of the following is correct ?

Liquid benzene burns in oxygen according to 2C6H6(l)+15O2 (g)→12CO2 (g)+6H2O(l) .How many litres of oxygen are required for complete combustion of 39 gms.Of liquid C6H6

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

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 quantum number which explains the line spectra observed as doublets in case of hydrogen and alkali metals and doublets and triplets in case of alkaline earth metals is

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

The heat of neutralization of strong acid and weak base is

A certain sample of gas has a volume of 0.2 litres measured at 1 atm. pressure and 00 C. At the same pressure but at 273 0c. Its volume will be

Exhausted permutit does not contain .... ion :

The element that can exhibit highest number of oxidation states amongst the following:

Absolute alcohol (100% alcohol) is prepared by distilling rectified spirit over:

Observe the following statements :I.    The physical and chemical properties of elements are periodic functions of their electronic configuration.II.    Electronegativity of fluorine is less than the electronegativity of chlorine.III.   Electropositive nature decreases from top to bottom in a group.The correct answer is :

Assertion (A): the molecularity of reaction is a whole number other than zero , but generally less than 3 Reactions (R): the order of a reaction is always whole number

Calorific value of producer gas is low because of

The gold numbers of three protective colloids A, B, and C are 0.05, 0.01 and 0.5 respectively. The decreasing order of their protective power is:

Which of the following is correct

The following reactions is an example of ..... reaction. C2H4Br2→C2H2

Three faradays of electricity are passed through molten Al2O3. Aqueous solution of CuSO4 and molten NaCl taken in three different electrolytic cells. The amount of Al, Cu and Na deposited at the cathodes will be in the ratio of

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

The Chemical reaction between NaS2O3 and I2 leads to the formation of

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