A to Z Exams

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

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

While phosphorus form PCl5, nitrogen does not form NCl5 because

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:

Observe the following statements regarding purification of bauxiteI. During Hall's process, silica is removed as Si (vapour)II. Bauxite ore contaminated with Fe2O3 is purified in Baeyer's processIII. During Serpeck's process, AlN is formedThe correct answer is

Nitro benzene on reduction with zinc and NH4CI gives

For the reaction 2SO2(g)+O2(g)2SO3(g) taking place in one litre vessel, the number of moles of SO2 ,O2,SO3 at equilibrium are 2,1 and 2 moles respectively, under a total pressure of 15 atm.The Kp of the reaction is

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

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

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

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

A certain mass of a gas occupies a volume of 2 L at STP. To what temperature the gas must be heated to double its volume, keeping the pressure constant

The active mass of 5.6 litres of O2 at STP is

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

Which one of the following equations represents the variation of viscosity coefficient (η) with temperature (T) ?

Which pair of oxyacids of phosphorous contain ‘P - H' bonds

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 bonds in K4Fe(CN)6 are:

Consider the two gaseous equilibria involving SO2 and the corresponding equilibrium constants at 298K SO2(g)+1/2O2(g)⇔SO3(g);K1 2SO3(g)⇔2SO2(g)+O2(g);K2 The values of the equilibrium constants are related by

138 g of ethyl alcohol is mixed with 72 g of water. The ratio of mole fraction of alcohol to water is

In Freundlich adsorption isotherm, the intercept is equal to

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

When aniline is treated with CHCI3 and KOH, the product is :

One Faraday of current was passed through the electric cells placed in series containing fused electrolytes with Ag+2,Ni2+,Cr3+ ions. The amount of Ag(at.wt=108), Ni(at.wt=59) and Cr(at.wt=52) deposited 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

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

5.85 gms of NaCl (Mol. wt. 58.5) is dissolved in water and the solution made up to 500ml; the molarity of the solution will be

The two sulphur atoms in Na2S2O3 have

Which of the following is correct ?

What is the quantity of electricity (in Coulombs) required to deposit all the silverfrom 250 mL of 1 M AgNO3 solution

The atomic numbers of elements X, Y and Z are 19, 21 and 25 respectively. The number of electrons present in the M shell of these elements follow the order

Which of the following pairs of ions are colourless ?

The heat of formation of SO2(g) is -297.8 kJ mol-1.The enthalpy change in the decomposition of 1 mole SO2(g) to its constituent elements is

Hydrolysis of chloroform with aqueous KOH gives finally

Observe the following reaction2A + B → CThe rate of C is 2.2 x 10-3 mol L-1 min-1.What is the value of - d[A]/dt (in mol. L-1min-1)

Method used for the concentration of tinstone ore is

The number of structural alcoholic isomers for C4H10O is

If the bond length and dipole moment of a diatomic molecule are 1.25 A and 1.0D respectively,what is the percent ionic character of the bond

One mole of fluorine is reacted with two moles of hot concentrated KOH. The products formed are KF, H2O and O2. The molar ratio of KF, H2O and O2 respectively is

Beryllium shows diagonal relationship with aluminium.Which one of the following similarity is not correct

What is the correct order of spin only magnetic moment (in BM) of Mn2+, Cr2+ and V2+ ?

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

Which of the following is not correct

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

Hydrolysis of sucrose with dilute aqueous sulphuric acid yields

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

8 gram of NaOH is mixed with 9.8 gram of H2SO4 in litre of solution the pH of the solution is

The degree of dissociation of an acid HA in 0.1 M solution is 0.1%. Its dissociation constant 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

If a reaction obeys the following equation. K=2.303/t log10a/a-x, the order of the reaction will be

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

Which of the following reacts with benzene in presence of anhydrous aluminum chloride and forms acetophenone ?

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 ?

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

At T (K), 100 L of dry oxygen is present in a sealed container. It is subjected to silent electric discharge, till the volumes of oxygen and ozone become equal. What is the volume (in litres) of ozone formed at T (K)?

Which of the following does not participate in carbylamine reaction?

'Natalite' is used as

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)

What is the volume (in litres) of oxygen required at STP to completely convert 1.5 mol of sulpher into sulpher dioxide

Which one of the following statements is correct

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

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

The vapour pressure of water at 230C is 19.8 mm. 0.1 mole of glucose is dissolved in 178.2 g of water. What is the vapour pressure (in mm) of the resultant solution

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

The conjugate acid of NH2- ion is:

Which of the following is not tetrahedral

During electrolytic reduction of aluminia,the reaction at cathode is

Which of the following is not correct

1 mole of PCl5 is heated with 0.2 mole of chlorine in a one litre vessel till equilibrium is established. At equilibrium if 0.8 mole of chlorine in the vessel, the value of equilibrium constant for the dissociation of PCl5 is (in moles-lit-1)

Which of the following is the anhydride of HNO3

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

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

Which of the following contains a coordinate covalent bond ?

Which of the following reagents can form a hydrazone with alkanone

The olefin which on ozonolysis gives CH3CH2CHO and CH3CHO is

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

Which of the following is used for making optical instruments ?

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

75% of first order reaction is completed in 32 minutes 50% of the reaction would have been completed in

75 ml of 0.2 M HCl is mixed with 25 ml of 1 M HCl. To this solution, 300 ml of distilled water is added. What is the pH of the resultant solution

A cylinder of gas contains 14.5 kg of butane. If a family needs 2.5x104 KJ of energy per day for cooking. Hoe long will the cylinder last. (Enthalpy of combustion of butane=2600 KJ/mole)

 Which of the following is not correct

Which of the following biomolecules acts as specific catalysts in biological reaction

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 :

Anhydrous Magnesium chloride can be prepared by heating MgCl26H2O

when acetaldehyde is heated with Fehling solution, a red precipitate is formed. Which of the following is that

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

Which one of the following sets correctly represent the increase in the paramagnetic property of the ions

What is the hybridization state of the central atom in the conjugate acid of NH3?

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

Which of the following brings about dry bleaching

Which of the following is a favourable factor for cation formation

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

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

pH of pure H2O at 250C is

Ordinary glass is a combination of the following

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

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

H3O++OH-→2H2O