General Questions and Answers

51 A mixture of HCOOH and H C2O4 is heated with concentrated H SO4 The gas produced is collected and on treating with KOH solution the volume of gas decreases by one sixth Calculate the molar ratio of the two acids HCOOH H2C2O4 in the original mixture

Following is the list of four halides Select correct sequence of increasing order of reactivity for SN reaction using the codes given below 1 C6H5 CH Br CH3 11 C6H5 CH Br III C6H5 CHI CH3 IV C6H5 CH I A 11 IV B IV II III C II IV I

If a copper rod free to move and rotate is brought in a region of a non uniform magnetic field then it will align itself 1 Along the direction of the magnetic field at a location where the magnetic field is strongest 2 along the direction of the magnetic field at a location where the magnetic field is weakest 3 perpendicular to the direction of the magnetic field at a location where the magnetic field is strongest 4 perpendicular to the direction of the magnetic field at a location where the magnetic field is weakest In a marriage hall there are 15 bulbs of 45 W 15 bulbs of 100 W 15 small fans of 10W and 2 heaters of 1 kW If the voltage of the electric main is 220 V then the minimum fuse capacity in A

The best procedure to use when filtering an aqueous solution to collect the precipitate is to Suball coal pl Wash the precipitate with a minimal amount of water Not wash the precipitate at all Use large volumes of water to ensure that all soluble matter is separated from the precipitate Warm the solution before filtering

3 36 32 10 ml of HCI 30 ml of HNO3 75 ml of 2 N 5 4 48 N 10 H SO4 are mixed together The normality a resulting solution is 1 0 02 N 2 0 5 N 3 0 2 N 4 0 025 N 33 A solution of NaOH is 4 g L 1 What volume of H L CTD will noutralize 50 ml of the al

5 In three beakers labelled as A B and C 100 mL of water 100 mL of 1M solution of glucose in water and 100 mL of 0 5 M solution of glucose in water are taken respectively and kept at same temperature water 1 M glucose solution 0 5 M glucose solution B Which of the following statements is correct C a Vapour pressure in all the three beakers is same b Vapour pressure of beaker B is highest c Vapour pressure of beaker C is highest d Vapour pressure of beaker B is lower than that of C and f hooker C is lower than that of A

c Surface tension 31 The molecular conductivity and equivalent conductiv are same for the solution of a 1 M NaCl c 1 MLa NO3 3 ativity is b 1 M Ba NO3 2 d 1 M Th NO3 4

palielam com excams review 64409 unanswered basic 21 You are provided with 1 mol each of nitric acid HNO sulphuric acid H SO and perchloric acid HCIO respectively in beakers A B and C Select the correct option from the following Atomic mass of N 14u S 32u C1 35 5u 1 A 2 A 3 A 4 A B B B B C

57 Which one is the most likely structure of CrCl 6H O if 1 3 of total chlorine of the compound is precipitated by adding AgNO to its aqueous solution 1 CrC1 6H 0 3 CrCL H O C2H O 2 Cr H O CI 3H O 4 CCI H O CL H O

Consider the following statements a NO2 is an odd electron molecule b 03 molecule has two resonating structures c PF5 follows octet rule The correct statements is are a and b only b and c only a and c only a b and c

If an antacid tablet releases 1 g of CO2 molar mass 44g mol What is the mass of NaHCO3 Molar mass 84g mol that is found in the tablet HCO3 aq H aq CO2 g H2O l 3 5 g O1 91 g 1 51 g

4 g of solid NaOH was dissolved in water and the solution was made up to 1000 ml The whole of this will neutralized completely 1 100 ml of 1 M H SO4 M H SO4 ho 2 20 ml of 2 5 M H SO4 3 20 ml of 1 5 M H SO4 4 30 ml of 5 M H SO4 08

Which of the following does not indicate a high level of pollutants or toxic substances 1 High DO value III High BOD value O O I II and III only II and IV only O II and III only III and IV only II High COD value IV High TLV

1 mass 2 volume 3 surface tension Xenthalpy Out of boiling point I entropy II pH III and e m f of a cell V intensive properties are 1 I II 2 I II III LOT I III IV librium involves 4 All of the above

Complete combustion of 1 80 g of an oxygen containing compound C H O gave 2 64 g of CO and 1 08 g of H O The percentage of oxygen in the organic compound is 1 51 63 2 63 53 3 53 33 4 50 33

Normal blood sugar level CHO in an adult human is 7mmolL If the blood sample of a contains 2000mg L then person 1 The person is non diabatic 2 The person is diabetic 3 Not enough information 4 None of the above

In an electron microscope electrons are accelerated to great velocities Calculate the wavelength of an electron travelling with a velocity of 7 0 megameters per second The mass of an electron is 9 1 x 10 31 kg A 1 0 x 10 13 m B 10x107m C 10 m

2 0 g sample contain mixture of SiO2 and Fe2 O3 on very strong heating leave a residue weighing 1 96 g The reaction responsible for loss of weight is Fe2 O3 s Fe3 04 s O2 g unbalance equation What is the percentage by mass of SiO2 in original sample 1 10 2 20 3 40 4 60

fo H H C CH3 aq alkaline KMnO A Which one of the following is true about this reaction 1 A is meso 2 3 butanediol formed by syn addition 2 A is meso 2 3 butanediol formed by anti addition 3 A is a racemic mixture of d and I 2 3 butanediol formed by anti addition 4 A is a racemic mixture of d and I 2 3 butanediol formed by syn addition

Equal volumes of three monobasic acids of pH 3 4 5 are mixed in a vessel The pH of the resultant solution will be log 3 7 0 57 3 91 5 27 6 81 3 43

2 Al O3 is reduced by electrolysis at low potentials and high currents If 4 0 10 amperes of current is passed through molten Al O3 for 6 hours what mass of aluminium is produced Assume 100 current efficiency at mass of Al 27 g mol a 8 1 x 10 g c 1 3 x 104 g g b 2 4 x 105 g d 9 0 10 g 2009

7 The solubility product of AgCl is 10 10 M2 The minimum volume in m of water required dissolve 14 35 mg of AgCl is approximately a 0 01 b 0 1 c 100 d 10 What is the molar solubility of Fe OH 2 Ksp 8 0 x 10 16 at pH 13 0

A solution contains 1 30 10 2 M potassium sulfide and 1 12 10 2 M sodium hydroxide Solid manganese II acetate is added slowly to this mixture A What is the formula of the substance that precipitates first formula B What is the concentration of manganese II ion when this precipitation first begins Mn M

A complex is repesented as CoCl3 xNH3 Its 0 1 molal solution in water shows AT 0 558 If the cryscopic and ebullioscopic constants for H O are 1 86 K kg mor and 0 52 K kg mor respectively identify the correct versions assuming 100 ionisation of the complex Hexaaminecobalt III chloride is the IUPAC name for the complex The above solution will boil between 100 C to 101 C The central metal ion is d sp hybridised The coordination sphere is incapable of exhibiting geometrical isomerism

In alkaline medium CIO oxidises H O to O and itself gets reduced to Cl How many moles of H O are oxidised by 1 mole of CIO 2 1 5 1 1 3 25 4 5

The ratio of difference in energy of electron between first and second Bohr s orbit to that between second and third Bohr s orbit is A 1 3 B 27 5 skipped

a 1 6 10 b 5 2 x 10 8 9 c 2 0 10 8 d 2 3 10 146 At 25 C Ksp for PbBr is equal to 8 10 5 If the salt is 80 dissociated what is the solubility of PbBr2 in mol litre 71 3 10 4 2 1 6 1 6 10 5 1 6 1 6 1 3 1 3 10 5 1 6 x 1 6 71 2 b c 10 4 0 8 0 8 d 147 What is the molar solubility of Mn OH Ksp 4 5 10 4 in a buffer solution containing

a 1 0 x 10 5 What is the molarity of F a 2 3 10 3 3 b 1 0 x 10 c 1 26 x 10 a 6 3 x 10 in a saturated solution of InF3 Ksp 7 9 x 10 10 b 8 3 x 10 3 c 1 0 10 3 d 7 0 x 10 What is the pH of a saturated solution of Cu OH Ksp 2 6 10

128 The solubility of different sparingly soluble salts are given as under Formula Type Solubility product 4 0 10 20 3 2 x 10 11 2 7 x 10 31 S No 1 2 3 AB A B AB 3 The correct increasing order of solubility is a 1 3 2 b 2 1 3 c 1 2 3 d 3 1 2

A metal M forms water soluble MSO4 and inert MO MO in aqueous solution forms insoluble M OH 2 soluble in NaOH Metal M is A Be skipped B Mg

A chemistry student needs 90 0 mL of dimethyl sulfoxide for an experiment By consulting the CRC Handbook of Chemistry and Physics the student discovers 3 that the density of dimethyl sulfoxide is 1 10 g cm Calculate the mass of dimethyl sulfoxide the student should weigh out Be sure your answer has the correct number of significant digits A Q 0x10

Given that i H g O2 g H O l AH 286 kJ ii C H g O g 2CO g H O 1 AH 1297 kJ 2 iii C H4 g 302 g 2CO2 g 2H O l AH 1410 kJ The enthalpy change for the process C2H2 g H g C H4 9 is O 173 kJ O 173 kJ O 346 kJ 346 kj

A 5 00 mL sample of solution has 2 8 x 104 g of calcium ions The ppm concentration is A B skipped C 18 ppm 56 ppm 2 8 x 10 ppm Class XI Chemistry Mole concept and Stoichiometry 4 for JEE BITSAT Exams Google Chrome e Class XI Chemistry Mole concep

8 Arrange the following in the increasing order of their solubility in n octane based on solute solvent interaction a KCI CH CN CH3OH Cyclohexane 2008 b KCI Cyclohexane CH3OH CH3CN c KCI CH OH CH3CN Cyclohexane 20 d KCI Cyclohexane CH CN CH3CN tulos A O 150910

3 The correct match between items of List I and List II is List I A Coloured impurity B Mixture of o nitrophenol and p nitrophenol P Q C Crude Naphtha R D Mixture of glycerol and sugars S 1 A R B S C P D Q 3 A R B P C Q D S List II Steam distillation Fractional distillation Charcoal treatment Distillation under reduced pressure 2 A P B S C R D Q 4 A R B P C S D Q

Predict whether the equilibrium constants for the following reactions should be greater than 1 or less than 1 a CdI2 s CaF2 s CdF2 s Cal2 s b Cul4 2 aq CuC14 3 aq c NH2 aq H2O 1 NH3 aq OH aq 1 point CuC14 2 aq CuI4 3 aq

1 2 3 Pressure False Phase diagram Determine the phase of matter or phases occurring at each labeled point on this phase diagram C A E B Temperature F G D 22 4 points What phase or phases of matter is point F Solid and liquid Gas Solid Liquid Solid liquid and gas Supercritical fluid Gas and solid Gas and liquid 00000000 Solid and liquid Supercritical fluid 23 4 points What phase or phases of matter is point G Liquid

lg N nagi 4 State the type of PH3 molecule according to the VSEPR theory 5 Considering x axis as the internuclear axis which out of the fo

Type your answer Cooling curve Determine the process occurring at each labeled point on this graph TEMPERATURE 2 3 COOLING TIME 4 5 7 4 points What process is occurring at point 3 Vaporization 000000003 Gas heating Solid heating Liquid heating Condensation Melting Freezing Gas cooling Solid cooling

1 4h 2 3h 3 2h CHEMISTRY Setting of plaster of Paris is 1 Dehydration 3 Combination with atmospheric CO 4 2 2 Oxidation with atmospheric oxygen 4 Hydration to yield another hydrate

5 points Calculate the amount of energy in kJ needed to heat 510 9 g of gold Au from 25 0 C to 1 113 0 C The melting point of gold is 1 064 8 C SAu s 0 147 J g C SAu I 0 128 J g C AH fusion 13 5 kJ mol Do not write unit in answer Report your answer with 1 place past the decimal point Type your answer

0 25 g of an organic compound on heating with conc HNO3 and silver nitrate in carius tube gave 0 20 g of AgBr then the percentage of bromine in the compound is Atomic Mass of Ag 108 u Br 80 u 28 34 6

Cooling curve Determine the process occurring at each labeled point on this graph TEMPERATURE 2 COOLING TIME 4 6 3 points What process is occurring at point 1 Freezing Liquid cooling 000000000 Vaporization Condensation Melting Liquid heating Solid heating Solid cooling Gas heating

140 The calculated spin only magnetic moment of Cr ion is 1 2 3 2 84 BM 3 87 BM 4 90 BM 5 92 BM 70 Brtne Hydro Hulep 1 Br 10 hydrolysis gives

KMnO4 mol wt 158 oxidizes oxalic acid in acidic medium to CO and water as follows 5C 042 2MnO4 16H 10CO 2Mn 8H O What is the equivalent weight of KMnO4 A 158 B 31 6 C 39 5 D 79 vidion ono molo of ferrous oxalate FeG 0 completely in acidic

3 The figure shows a disc of radius 3R from which a circular hole of radius R is cut as shown in the figure The distance of the centre of mass of the remaining object from the point O is R R 6 A block A of mass 2m is hanging from a vertical massless spring of spring constant and is in 74 3R R Rm

Select the incorrect statement among the following Calcium plays important role in neuromuscular function Calcium concentration in plasma is regulated by calcitonin and parathyroid hormone All enzymes that utilise ATP in phosphate transfer require magnesium as the cofactor Sodium ions are the most abundant cations within cell fluids

The IUPAC name of the following compound is CONH CHO 1 2 Carbamoylhexanal 3 2 Methy 6 oxohex 3 enamide 2 2 Carbamoylhex 3 en 4 6 keto 2 methyl hexa

33 A hydrocarbon contains 80 of carbon then the lukt hydrocarbon is 1 CHA 3 C H 6 2 C H 4 C H

1 In system A s 2B g 3C g at equilibrium if concentration of C is doubled then concentration of B at equilibrium 1 Double its original concentration 2 Half its original concentration 3 2 2 its original concentration 4 its original concentration 2 concer