General Questions and Answers

For the equilibrium 2SO g O g 2SO3 g K 245 at 100 K The equilibrium concentrations are SO 0 204 M 0 0 0264 M and SO3 0 368 M Suppose that the concentration of SO is suddenly halved calcula Qc and use it to show that the forward reaction takes place to reach a new equilibrium

13 is Excess of NaOH aq was added to 100 mL of FeCl3 aq resulting into 2 14 Given molar mass of Fe 56 g mol 1 and molar mass of Cl 35 5 g mol JEE MAIN 1 1 8 M 2 0 6 M 3 0 2 M 4 0 3 M completely to CO2 and H O The empirical formula of compound CxH O is 1 C H603 The ratio of mass percent of C and H of an organic compound CyHyO is 6 1 If one molecule of the above compound CxHyO contains half as much oxygen as required to burn one molecule of compound CH 2 C H4O JEE MAINS 2018 4 C H4O3 O 3 C H4O2 our solution of KI INS ONLINE 2019

A solution containing 2 7 x 10 3 mol of A2 ions required 1 6 10 3 mole of MnO4 for the oxidation of A2 to A03 the medium use is Question Type Single Correct Type 1 Neutral 2 Acidic 3 Strong basic

750 waves of an electromagnetic energy radiation passes in one minute from a point then what will be the wavelength of radiation Question Type Single Correct Type 1 4 105 m 2 2 4 107 m 3 4 16 x 10 8 m

The enolic form of acetone contains Question Type Single Correct Type 1 9 o bonds 1 bond and 2 lone pairs 2 8 o bond 2 bond and 2 lone pairs 3 10 o bond 1 bond and 1 lone pair

Based upon the derivation shown for the freely jointed chain model derive an equation for the square of the average end to end distance for a new polymer architecture In this polymer architecture the chain is composed of two different repeat unit types A and B Here the number of repeat units of A are n and the number of repeat units of B are ng Moreover the lengths of the respective units are 1 and 1 Finally the bond angle between A links is 0A and the average bond angle between B links is 0 The angle between A and B links and B and A links is the same and this can be represented by OAB If this is the case the expression for the square of the average end to end distance can be represented by which of the following A r n l ngl 3 B r n nl 2n nll C r nal ngl 2nAnglalB COS OAB 1 cos 1 cos D r n 1 COSA nal 1 COSA 1 cos 1 cos

29 5 mole of a mixture of FeSO4 NH4 2SO4 6H 0 and Fe2 SO4 3 required 400 ml 0 5M KMnO for complete oxidation in acidic medium Then of moles of Fe SO4 3 in the mixture is 4 1 20 1289 2 40 3 60 4 80

The reaction of toluene with CI in presence of FeC1 gives X and reaction in presence of light gives Y Thus X and Y are 1 X Benzyl chloride Y m chlorotoluene 2 X Benzyl chloride Y o chlorotoluene 3 X m chlorotoluene Y p chlorotoluene 4 X o chlorotoluene and p chlorotoluene Y trichloromethyl benzene

Which of the following complete ions is expected of absorb visible light At no of Zn 30 Sc 21 Ti 22 Cr 24 Question Type Single Correct Type 1 Sc H O 3 NH3 3 2 Ti en 2 NH3 2 4 3 Cr NH3 6 A Zn NH 2

For a reaction A B E 10 kJ mol 1 AH 5 KJ mol 1 Thus potential energy profile for this reaction is PE PE PE PE B A Reaction progress B A Reaction progress M Reaction progress A A B Reaction progress

Based on below graph plotted between boiling point and mole fraction in liquid phase for the liquid binary mixture Comment on the liquid mixt Ideal solution Showing negative deviation from Raoult s law Showing positive deviation from Raoult s law Mixture of two immiscible volatile liquids B P X 1 X 1

Which of the following products are formed reacts with when potassium bromide potassium permagnate in alkaline medium Question Type Single Correct Type 1 BrO3 MnO2 2 BrO4 Mn 2

An aromatic monoacidic base has 77 42 carbon and twice as much nitrogen by weight as hydrogen 1gm of chloroplatinate of this base on ignition gave 0 327gm of Pt Find the molecular weight W of the base in gm mol From the above two data find molecular formula CxHyNz of the given Base What is the value of x

66 Consider the following reactions at 1100 C 1 2C 0 2CO AG 460 kJ mol II 22n O 2ZnO AG 360 kJ mol D Based on these select correct alternative a zinc can be oxidised by CO AIEEE 2002 b zinc oxide can be reduced by carbon c Both a and b d None of the above

1 54 9 g 2 5 4 g 3 10 8 g 4 108 0 g 7 The increasing order of basicity for the following intermediates is from weak to strong CH H C e T CH3 i H C CH CH HC E 1 v iii ii iv i 3 v i iv ii iii CH iii iv 2 iii iv ii i v 4 iii i ii iv v

13 The work done during the expansion of a gas from a volume of 4 dm to 6 dm against a constant external pressure of 3 atm is 2004 a 608 J b 304 J c 304 J d 6 J

9 4 The correct order of equivalent conductances at infinite dilution in water at room temperature for H K CH3COO and HO ions is a HO H K CH3COO b H HO K CH3COO c H K HO CH3COO H rr V U WB FF

43 In which one of the following the number of protons is greater than neutrons but number of protons is less than the number of electrons Kerala PMT 2008 205 0 b SO 2 c H O d s Se OH mort p n P

a moles of K2Cr2O7 are needed in acidic medium for the oxidation of 9 moles of ethanol to acetic acid An unknown metal chloride undergoes reduction reaction with Mg producing metal and MgCl2 Experiments show that 52 4 g of metal chloride reacts with 9 6 g of Mg according to above reaction The equivalent weight of metal in the given metal chloride is b b Report your answer as

Total vapour pressure of mixture of 1 mole of A P A 150 torr and 2 mol B P B 240 torr is 220 mm Hg In this case Question Type Single Correct Type 1 2 3 4 There is positive deviation from Raoult s law There is negative deviation from Raoult s law There is no deviation from Raoult s law None of these

For a chemical reaction 2X Y Z the rate of appearance of Z is 0 05 mol L 1 per min The rate of disappearance of X will be Question Type Single Correct Type 1 0 05 mol L 1 per hour 2 0 05 mol L 1 per min 3 0 1 mol L min 1

A B D small heat Two moles of an ideal mono atomic gas undergoes a thermodynamic reversible process during which in each small step dQ absorbed by gas dW small work done by gas dU small internal energy change of gas are related to each other as dQ dW dU 2 Then heat capacity of the gas during the process is R is universal gas constant 5R 2 3R 3R 2 None of these

58 Igofan impure sample of calcium carbonate containing no thermally decomposable impurities on complete thermal decomposition gave 0 33 g of carbon dioxide gas The percentage of impurity in this sample is Atomic masses of C O and Ca are respectively 12 16 anc 40 g mol a 25 c 30 b 201 d 33 J K CET

Lt x y 3 x y HEAT OF FORMATION 107 Since the enthalpy of the elements in their standard states is taken to be zero The heat of 108 Reaction H s I g formation AH of compounds 1 Is always negative 2 Is always positive 3 Is zero 4 May be positive or negative 2 x y 4 More data required 242 2HI AH 12 40 kCal According to this heat of formation of HI will be 1 12 40 kCal 3 6 20 kCal abe of akso 1 3201 kJ 109 At 300K the standard enthalpies of formation of CH COOH CO2 and H Oare 408 393 and 286 kJ mol respectively Calculate the heat of combustion of benzoic acid at contant volume 2 3199 75 kJ L 3201 kJ 4 3199 75 kJ 2 12 40 kCal 4 6 20 kCal Brow 114 C C fo 1 115 TI C 2 he 1 3 116 T EES m m 1 2 117

Which of the following combination of statements is true regarding the interpretation of the atomic orbitals Jan 9 2019 II a An electron in an orbital of high angular momentum stays away from the nucleus than an electron in the orbital of lower angular momentum b For a given value of the principal quantum number the size of the orbit is inversely proportional to the azimuthal quantum number c According to wave mechanics the ground state an gular momentum is equal to h 2 d The plot of y vs r for various azimuthal quantum numbers shows peak shifting towards higher r value a a d b a b

Identify the basic salt solution KCI aq ZnCl aq NaNO3 aq LiC H3O2 aq CaBr aq According to Lewis theory H is an acid because it accepts electron pairs H is a base because it donates electron pairs H is an acid because it donates electron pairs H is a base because it accepts electron pairs

Total vapour pressure of mixture of 1 mole of A 150 torr and 2 mol B P B 240 torr is 220 mm Hg In this case PA Question Type Single Correct Type 1 There is positive deviation from Raoult s law 2 There is negative deviation from Raoult s law 3 There is no deviation from Raoult s law

55 An unsaturated hydrocarbon X absorbs two hydrogen molecules on catalytic hydrogenation and also gives following reaction Az NH 0 2 10 A X 56 B 3 oxo hexanedicarboxylic acid X will be 1 2 3 The weight of cilvor at yet 10 dienlaged by a quantity of electricity which dienlange 560 ml of a at

10 2 marks The boiling point of a pure solvent is 353 23 K When 90 grams this solvent is used to dissolve 1 80 g of a non volatile solute its boiling pa is raised by 0 87 K Find the molar mass of the solute Boiling point elevati constant Kb for the solvent is 2 53 K kg mol

3 Define the shift of the equilibrium for the following reaction CO2 g C s 2CO g AH 172 kJ in case of a Increase of temperature Explain your answer b Decrease of pressure Explain your answer Write the expression for the equilibrium constant of the reaction

Max score 2 Neg score 0 5 An atom s emission spectrum can be observed in ground state An emission spectrum from an atom will contain all wavelengths of energy Electrons in the 2s orbitals of Boron and Carbon have same amount of energy Gamma rays are higher in energy than Infrared waves

The phosphorus in a 0 2300 g sample was precipitated as the slightly soluble NH4 3PO4 12 Mo O3 This precipitate was filtered washed and then redissolved in acid Treatment of the resulting solution with an excess of Pb resulted in the formation of 0 2922 g of PbMo 04 Express the results of this analysis in terms of percent P2O5

The pK value for HCN is 9 40 Would a buffer prepared from HCN and KCN with a pH of 8 90 be considered to be an effective buffer A buffer in which the mole ratio of KCN to HCN is 1 8 has a pH of 9 65 Would this buffer solution have a greater capacity for added acid H O or added base OH

A bar magnet is held at a right angle to a uniform magnetic field The couple acting on the magnet is to be halved by rotating it from this position The angle of rotation is 1 60 2 45 3 30 4 75 A battery of internal resistance 40 is connected to the network of resistance as shown in the figure To

The vapour pressure P of three aqueous solutions X Y and Z of same solute but with different concentrations are plotted against temperature T in Kelvin X Y Z a The concentration of these solutions are in the order A X Y Z C Z Y X B X Y Z D X 7 Y

Q 4 Enthalpy of reaction for N g 3H2 g 2NH3 g is 92 KJ What will be the effect of increasing the temperature on the extent of reaction Max score 2 Neg score 0 5 equilibrium will shift towards the reactants equilibrium will shift towards the product No change will occur as all reactants and products are gaseous equilibrium will move equally towards roactants and products

Consider the following groups 1 OAC II OMe IV O SO2 CF3 III O SO Me The order of leaving group nature is Question Type Single Correct Type 1 V 2 IV III 3 IV

Q 6 Select the reaction which can not be employed for precipitation titration Max score 2 Neg score 0 5 2 AgNO3 CaCl2 Ca NO3 2 10 CO2 g 8 H O K SO4 BaCl2 BaSO4 s 2 KCI 2MnO4 5 H C2O4 6 H 2 AgCl s 2 Mn AgNO NaSCN AgSCN s NaNO

Q 10 Presence of a catalyst in a reaction will affect the equilibrium in the following manner Max score 2 Neg score 0 5 equilibrium will move towards the reactants equilibrium will move towards the products helps to reach the equilibrium faster Effect on equilibrium can not be determined

Problem 11 How many carbon atoms are present in 0 35 mole of C6H12O6 Problem 12 How many nitrogen atoms are in 0 25 mole of Ca NO3 Problem 13 How many molecules of water are present in the one mL of water Problem 14 How many molecules are present in one mL of water vapours of STF Problem 15 What is the weight of 3 01 x 1023 molecules of ammonia

Q18 Rajat took 100 g of 50 w w sugar solution He divided the solution into 4 equal parts He added 5 g of sugar in 1st part A and 20 g of water in 2nd part 8 then he mixed these two parts and labelled the solution as C The concentration w w of solution C is A 60 B 40 30 D 55 Answer B 4

A sample of 100 ml of 0 10 M acid HA 1 10 5 is titrated with standard Ka 0 10 M KOH How many ml of KOH is required to be added when the pH in the titration flask will be 5 00 A 0 B C 10 100 D 50

Problem 13 How many molecules of water are present in the one mL of water Problem 14 How many molecules are present in one mL of water vapours of ST Problem 15 What is the weight of 3 01 x 1023 molecules of ammonia Problem 16 If it requires one second to count four wheat grains calculate the ti

c 40 mL 30 mL 30 mL d 55 mL 20 mL 25 mL 102 A bottle of an aqueous H O2 solution is labelled as 28 V H O2 and the density of the solution in g mL is 1 25 Choose the correct option a Molality of H O2 solution is 2 b Molarity of H O2 solution is 5 d None of these c Molality of H O2 solution is 2 15 103 The impure 6 g of NaCl is dissolved in water and then treated with excess of silver nitrate solution The mass of precipitate of silver chloride is found to be 14 g The purity of NaCl

a 1 79 b 2 143 c 1 951 d None of these 91 0 2 mole of HCl and 0 2 mole of barium chloride were dissolved in water to produce a 500 mL solution The molarity of the Cl ions is a 0 06 M b 0 09 M c 1 2 M d 0 80 M 92 Calculate the mass of anhydrous HCl in 10 mL of concentrated HCl density 12 g ml

20 ml of 0 1 M weak acid HA has Ka 10 5 is mixed with Solution of 10 ml of 0 3 M HCl and 10 ml of 0 1 M NaOH Find the value of A HA A in the resulting Solution A 2 104 B 2x10 5 C 2x10 D 0 05

HX is a non volatile weak acid with a K of 10 9 It reacts with NaOH to form a salt Nax The osmotic pressure in atm of a 0 001 M Solution of NaX at 298 K is Equal to the osmotic pressure A of 0 001 M NaCl at the same temperature B C D Greater than the osmotic pressure of 0 001 M NaOH at the same temperature Twice the osmotic pressure of 0 001 M NaOH Less than the osmotic pressure of 0 001 M NaCl

Which of the following statement s is are correct 1 The pH of 1 0 10 8M solution of HCI is 8 2 The conjugate base of H PO is HPO 3 Autoprotolysis constant of water increases with temperature 4 When a solution of a weak monoprotic acid is titrated against a strong base at half neutralization point pH pk

Problem 7 Problem 8 Problem 9 What is the weight of one atom of H in g at wt of H 1 008 How many g atoms and no of atoms are there in 120 g carbon Calculate the mass in g of a 2 mole of CO b 2 N molecules of CO

1 2 3 75 Identify the product in the following reaction 3 4 5 Tribromoaniline 1 3 4 5 Tribromo nitroaniline 3 3 4 5 Tribromophenol 4 All of these 2 1 2 3 Tribromobenzene 4 2 4 6 Tribromobenzene