A to Z Exams

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

Which of the following statements is correct

All the three oxygen atoms of ozone are utilized in the oxidation of

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

Chemisorption involves

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

Carbogen to

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

The gas that is used for sterilizing water 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 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

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

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

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

The solubility of the impurities in the metal in molten and solid states is different. The principle involved in the refining of metal is

If 20 mL of 0.4 N NaOH sol ution completely neutralised 40 mL of a dibasic acid, the molarity of the acid solution is :

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

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

Which of the following is not correct

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

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 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

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

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

which of the following is not correcr?

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

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

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

X,Y,Z hydrocarbons molecular formula are CH4, C2H4, C2H2, these three are passed through porcelain tube containing ammonical cuprous chloride. The out coming gases would be

Assertion(A): The molecularityof reaction is a whole number other than zero, but generally less than 3. Reason(R): The order of a reaction is always a whole number

3.42g of substance of molecular weight 342 is present in 250g of water.Molality of this solution is

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

Among  the following, which is water insoluble

Which of the following is not an air pollutant

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)

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)

The molarity of pure water is:

Which of the following is not tetrahedral

Which of the following is not a lipids

Which of the following statements is NOT correct?

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

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

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)

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

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

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)

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

The oxidation states of nitrogen in NH4NO3 is /are

The bonds in K4Fe(CN)6 are:

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

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

Hybridization at 2nd carbon in CH2 = CH – CH3 is

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

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

The rate constant of a reaction increased by 3 times for every 100C rise of temperature uniformly in the range 200C to 800C, if the rate of constant at 300C is K, what is its value at 600C

Which of the following reactions can produce aniline as main product

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 active mass of 5.6 litres of O2 at STP is

For a reaction A+B→ products,the rate of the reaction was doubled.When the concentration of A was doubled.When the concentration of A and B were doubled.The order of the reaction with respect to A and B are

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

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

The correct order of reducing abilities of hydrides of V group elements is

In the extraction of sodium by Down's process, cathode and anode are respectively:

Identify the correct order in which the covalent radius of the following elements increasesI. TiII. CaIII. Sc

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

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

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

The chemical formula of feldspar is

CFCl3 is responsible for the decomposition of ozone to oxygen. Which of the following reacts with ozone to form oxygen ?

A and B are ideal gases. The molecular weights of A and B are in the ratio of 1 : 4. The pressure of a gas mixture containing equal weights of A and B is P atm. What is the partial pressure (in atm) of B in the mixture ?

The compound prepared by a substitution reaction of benzene 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

Alcohol manufactured from water gas is

The equilibrium constant for the reaction is 6.The initial concentration of each of CH3COOH and C2H2OH is two(mole/lit).What is the concentration of CH3COOC2H5 at equilibrium in moles /lit

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

When ethyl alcohol reacts with bromine in the presence of alkali the compound formed

The final product formed on the strong heating of H3BO3

Method used for the concentration of tinstone ore is

Anhydrous Magnesium chloride can be prepared by heating MgCl26H2O

Hydrolysis of trichloro methane with aqueous KOH gives

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

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

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

Which of the following is not correct

0.84 g of metal carbonate reacts exactly with 40 mL of N/2 H2S04. The equivalent weight of the metal carbonate is :

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

Which one of the following statements is correct

How many electrons are present in the M shell of an atom of an clement with atomicnumber 24 (Z = 24) ?

When a copper wire is dipped in a aqueous AgNO3 solution, the solution turns blue,The reason for this is

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

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.

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 not obtained when methyl chloride and n-propyl chloride react with sodium in dry ether

The standard reduction potentials of Zn2- | Zn, Cu2+| Cu and Ag+| Cu and Ag+| Ag are respectively -0.76, 0.34 and 0.8 V. The following cells were constructed :1) Zn | Zn 2+||Cu 2+| Cu2) Zn | Zn 2+||Ag +| Ag3) Cu | Cu 2+||Ag +| Agwhat is the correct order of Eocell of these cells?

Which one of the following reactions does not form gaseous product

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

Which of the following brings about dry bleaching

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