General Questions and Answers

B The total vapour pressure of a solution of methanol and ethanol in an ideal solution is given by P 135 x 100 where a mole fraction of methanol Pure state vapour pressure of methanol is 1 235 mm g 2 100 mm g AOF

693 pm In a solid AB having the NaCl structure A atoms occupy the corners of the cubic unit cell If all the face centred atoms along one of the axis are removed then the resultant stoichiometry of the solid is a AB 2 c A4 B3 2X23 b A B d A3 B 4 ili

24 A B C are the elements such that A on r eaction with air produces dazzling white fla me B is used in rubber industry for hardening C acts as a conductor with rise in temperatur e Then A B C are 1 metals 2 metal and non metal respectively 3 non metal metal metalloid respectively 4 metal non metal metalloid respectively

The number of moles of Br produced when two moles of potassium permanganate are treated with excess potassium bromide in aqueous acid medium is A 1

Consider the following reaction C A B 2 The heat required in the above reaction at 300 K is 240 J If x J would be the value of heat evolved a X 310 K then the value of is 10 Cp A 35 JK 1 mol 1 Cp B 30 JK 1 mol 1 Cp C 32 JK 1 mol 1

74 The tests performed on compound X and their inferences are Test Inference 1 2 4 DNP test coloured precipitate 2 iodoform test yellow precipitate 3 Azo dye test no dye formation NH OH 1 3 NH CH3 CHO 2 H C H C CH COCH CH CHO

7 Among the colloids cheese C milk M and smoke S the correct combination of the dispersed phase and dispersion medium respectively are 1 C solid in liquid M solid in liquid S solid in gas 2 C solid in liquid M liquid in liquid S gas in solid 3 C liquid on solid M liquid in lid S solid in gas 4 C liquid in solid M liquid in liquid S solid in gas An organic compound contains C 40 H 13 33 and N 46 67 Ite empirical formula

For the decomposition that 2N205 9 4NO g O g activation energy Ea 1 N 05 g 2NO g 2 02 g activation energy Ea then of N O5 g it is given Question Type Single Correct Type 1 Ea 2Ea

If the ionic radii of K and F are nearly the same 1 54 then the atomic radii of K and F respectively are Question Type Single Correct Type 1 2 3 4 1 34 1 34 1 80 1 08 1 54 0 72 1 96 1 96

14 For the reaction 2A g B g 3C g 4D g Two moles each of A and B were taken into a 1L flask The following must always be true when the system attained equilibrium a A B b A B c B C d A B C D

In Haber process 30 litres of dihydrogen and 30 litres of dinitrogen were taken for reaction which yielded only 50 of the expected product What will be the composition of gaseous mixture under the aforesaid condition in the end a 20 litres ammonia 20 litres nitrogen 20 litres hydrogen 10 litres ammonia 25 litres nitrogen 15 litres hydrogen c 20 litres ammonia 10 litres nitrogen 30 litres hydrogen d 20 litres ammonia 25 litres nitrogen 15 litres hydrogen 2003 F

A 60 m sample solution of KI was electrolysed for 579 sec using a 5 amp constant current The I2 produced completely reacted with 0 20M sodium thiosulphate solution and unreacted KI solution required 30ml of 0 04M acidic solution of KMnO4 If the original molarity of KI solution can be expressed in scientific notation as Y x 10 Calculate the value of Y

Let the solubilities of AgCl in H 0 0 01M CaCl 0 01M NaCl and 0 05M AgNO3 be S S2 S3 S4 respectively What is the correct relationship between these quantities Question Type Single Correct Type 1 2 3 4 S S S3 S4 S S3 S S4 S4 S2 S3 S S4 S3 S2 S

The radius of Li Atomic number of La 57 is 1 06 A Which one of the following given values will be closest to the radius of Lu3 Atomic number of Lu 71 A B 1 60A 1 40A

7 An experiment was carried out to determine desorption efficiency I placed 25 L of hydrochloric acid solution 4350 ppm onto 100 mg of silica gel The next day I desorbed the HCI with 10 mL of standard eluent 5 mL of this solution was found to contain 42 g of hydrogen chloride What is the desorption efficiency 5 marks

A mixture of salts was treated to determine the barium content A 0 230g sample was dissolved and treated with excess potassium chromate The precipitate of Ba 04 was dissolved in dil HCI to convert BaCrO4 to Cr 0 anion The solution treated with excess sodium iodide and tri lodide produced was titrated with 21 mL of 0 095 M sodium thiosulphate Calculate the of BaCl2 2H O in the sample given Molar Mass of BaCl2 2H20 244 B C 30 25 15 12

Compound Enthalpy of formation kJ mol Using these data calculate the enthalpy of reaction for N Q g 300 e Neb 3 000 CO 00 110 0 393 0 81 0 N O N O 9 7 131 1AU

The energy absorbed by each molecule A of a substance is 4 4 x 10 19 J and bond energy per molecule is 4 0 x 10 19 J The kinetic energy of the molecule per atom will be a 2 2 10 J c 4 0 10 20 J b 2 0 10 J d 2 0 10 20 J 2009

For an enzyme substrate system obeying the simple Michaelis Menten mechanism the rate of product formation when the substrate concentration is very large has the limiting value 0 02 mol dm At a substrate concentration of 250 mg dm the rate is half this value Calculate k k assuming k k

Limiting equivalent conductance of Ba OH 2 1 BaCl and NH4Cl is 500 300 100 ohm then calculate value of 2 NH OH eq NH4OF NH CH 22 52 1 200 2 300 3 500 4 900 The conductivity of a saturated solution of CSI3 is 3 06 x 10 ohm m and its molar conductance is 1 53 ohm m mol The value of Ksp for CsI is 1 4 x 10 2 2 4 10 10 3 2 5 10 4 2 5 10 13

If 0 224 L of H gas is formed at the cathode the volume of O gas formed at the anode under identical conditions is 1 0 224 L 3 0 112 L 2 0 448 L 4 1 12 L

A solution contains Na2CO3 and NaHCO3 10 mL of the solution required 2 5 mL of 0 1 M H SO4 for neutralisation using phenolphthalein as indicator Methyl orange is then added when a further 2 5 mL of 0 2 M H SO4 was required The amount of Na CO3 and NaHCO3 in 1 litre of the solution is 1 5 3g and 4 2g 2 3 3g and 6 2g 3 4 2g and 5 3g 4 6 2g and 3 3g

Elements A and B form two compounds B A and B A 0 05 moles of B A weight 9 0 g and 0 10 mole of B A weight 10 g atomic weight of A and Bare 2 3 1 20 and 30 3 40 and 30 2 30 and 40 4 30 and 20

73 A chiral CsH10O ether reacts with hot HI to give a CsH 0l2 product Treatment of this with hot KOH in ethanol produces 1 3 pentadiene What is the structure of the original ether A B O D

46 A nitrogeneous substance X is treated with HNO and the product so formed is further treated with NaOH solution which produces blue colouration X can be A CH3CH NH2 C CH3CH ONO B CH3CH NO D CH3 2CHNO2

Consider a titration of potassium dichromate solution with acidified Mohr s salt solution using diphenyl amine as indicator The number of moles of Mohr s salt required per mole of dichromate 1 3 3 5 4 6 2 4

74 Which of the following on treatment with CH CH produce gas es iii OH iv Na in liq NH3 1 NH ii CH3 A ii iii and iv C i ii and iv B i ii and iii i iii and iv

An electron is confined to a two dimensional infinitely deep potential well of width a 45 pm Compute the de Broglie wavelength of the electron when it is in the 2 excited state 30 pm b 75 pm C 60 pm d 90 pm

The bromination reaction of benzene ring requires AlBr3 or lewis acid but in case of phenol it takes place even in absence of AlBr3 or lewis acid This is due to Question Type Single Correct Type 1 2 OH group is highly activating thus facilitate on easy electrophilic substitution reaction 3 reaction is taking place at ortho para position 4 Bromination of aromatic ring is fastest electrophilic substitution reaction Bromination reaction form precipitate of

and The solubility of CaCO3 is 8mg L Calculate the Ksp of BaCO3 when Na2CO3 is added slowly a solution containing equimolar concentration of Ca and Ba2 no precipitate is formed until 80 of Ba has been precipitated as BaCO3 A 1 1 x 10 10 B 5 0 10 10 C 6 4 x 10 10 D 11 x 10 9

A welding fuel gas contains carbon and hydrogen only Burning a small sample of it in oxygen gives 3 38 g carbon dioxide 0 690 g water and no other products A volume of 10 0 L measured at NTP of this welding gas is found to weigh 11 6 g Calculate i empirical formula ii molar mass and iii molecular formula of the gas Calculation of mass percent of carbon and hydrogen CO C

If the number of oxygen atom s present in hydrated P is H SO P Q H SO KI Option A B 10 18 Q BaSO H O K SO4 H O R Blue colured Starch

55 Which optically active compound on reduction with LiAlH4 A CH3 CH COOH OCH3 C CH CH CH COOH CH OH will give optically inactive compound B CH3 CH CH COOH 1 OH D CH CH CH COOH 1 OH

Three reactions involving H PO4 are given below i H3PO4 H O H O H PO4 2 4 ii H PO4 H O H O HPO iii H PO HO 0 HO 0 H3PO4 In which of the above does H PO4 act as an acid A i only B ii only C i and ii D iii only

Assuming that petrol is octane CH and has density 0 8 g mL 1 425 litre of petrol on complete combustion will consume on ga 1 50 mole of O 3 125 mole of O 2 100 mole of 0 4 200 mole ofO 2

If pkw of water is obtained 13 48 on increasing temperature then H ion concentration in water will be Question Type Single Correct Type 1 2 3 4 10 7 3 x 10 13 3 4 x 10 13 1 8 x 10 7

In an experiment it showed that 10 mL of 0 05 M solution of chloride required 10 mL of 0 1 M solution of AgNO3 which of the following will be the formula of the chloride X stands for the symbol of the element other than chlorine a X Cl c XC14 b XCl d X Cl

A mixture of H SO4 and H C O4 and some inert impurity having mass 2 g is dissolved into water and solution made to 1 L 100 mL of this solution required 40 mL of 0 1 M NaOH solution for complete neutralization In another experiment 100 mL of the same solution required 40 mL of 0 01 M KMnO4 in acidic medium Select the incorrect statement H SO4 present in mixture is completely neutralize by 10 mL of 1 M Ca OH 2 solution Mol of H SO4 and H C2O4 are equal Mass of H SO4 in mixture is more than mass of H C 04 Mass of H C2O4 in mixture is 50

3 Alkyl halide undergoes sequence of reaction to form primary amine Identify X and Y in the following sequence C H Br Product C H NH 1 X KCN Y H 0 3 X CH CI Y AICI HCI 2 X KCN Y LiANH 4 X CH NH Y HNO

For an enzyme catalyzed reaction the slope and the intercept of Lineweaver and Burk plot are 10 2 s and 10 M s respectively If the initial concentration of the enzyme Eo 10 6 M and k k 1000 calculate the value of k

In a different experiment the analyst has developed a new method for the determination of manganese in the soil extract However there was no known linear relationship between measurement signal and manganese concentration yet Therefore the analyst decided to perform a standard addition calibration experiment similar to that for strontium above Explain why this is an appropriate action or otherwise

The energy of the electron in the first orbit of Het is 871 6 x 10 20 J The energy of the electron in the first orbit of hydrogen would be Question Type Single Correct Type 1 2 3 4 871 6 10 20 J 435 8 x 10 20 J 217 9 x 10 20 J 108 9 10 20 J

compounds is treated with Br in the presence of FeBr 2014 a b c d Br Br CH CH Br CH V Br CH3 CH3 O CH3 CH3 CH3 and CH3 CH and and and Br CH Br CH CH3 Br CH3 CH Br CH3 CH CH3

Consider this equilibrium for which AH 0 HgO s 41 aq H O l Hg2 aq 2OH aq which changes will increase the equilibrium concentration of Hgl4 I Increasing the mass of HgO s present II Increasing 1 III Adding 1M HCI Question Type Single Correct Type 1 2 3 A I only II only II and III only III and III

2017 128 23 Solubility of which among the following solids in water changes slightly with temperature a KNO3 b NaNO3 c KBr d NaBr MHT CET

9 Electronic transition in He ion takes from n to n shell such that 2n 3n 18 2n 3n 6 What will be the total number of photons emitted when electrons transit to n shell 1 21 2 15 3 20 4 10

a A 2 36 g sample of dolomite containing CaCO3 and MgCO3 were dissolved in 700 mL of decinormal solution of HCI The solution was diluted to 2 5L and 25mL of this solution required 20 mL 0 01N NaOH solution for complete neutralisation Compute the composition of the ore 7

in this reaction Problem 2 1 7 g of silver nitrate dissolved in 100 g of water is taken 0 585 g of sodium chloride dissolved in 100 g of water is added to it and chemical reaction occurs 1 435 g of silver chloride and 0 85 g of sodium nitrate are formed Justify that the data obey law of conservation of mass

INSTRUCTION Question given below has four answer options out of which ONLY ONE is correct Choose you will be awarded 4 Marks and for WRONG answer there is a negative marking of 1 Mark No marks wi The most stable and the least stable carbunion among CH CH CH are respectively A ILI OLII CH CH CH CH CH IV B III IV D LIV

In sommerfeld s modification of Bohr s theory the trajectory of an electron in a hydrogen atom is A B C a perfect ellipse a closed ellipse like curve narrower at the perihelion position and flatter at the aphelin position a closed loop on a spherical surface