Physical Chemistry Questions

Q16 The arrangement ABC ABC is referred to as 1 octahedral close packing 2 hexagonal clase packing 3 tetrahedral close packing 4 cubic close packing 1 2 55 3 From NCERT 4

2 5 pts each Using the smallest possible whole numbers balance the following equation You need to drag and drop all correct coefficients including 1 As4S6 s O g As406 aq SO2 aq

Q3 Metals have conductivity of the order of ohm cm 1 10 2 2 108 3 10 4 10 6 1 2 53 From NCERT 3 4

For the elementary reaction mA nB products A is present in excess and when the concentration of B is changed from 0 01 to 0 02 the rate of reaction becomes 4 times then the rate law determined experimentally can be

The following graphs represent the behavior of BaCO3 under different circumstances In each case the vertical axis indicates the solubility of the BaCO and the horizontal axis represents the concentration of added reagent Solubility O Solubility Conc 1 Which of the following is are correct Solubility Conc ii All of these Conc Curve i represents addition of Na CO3 to a solution containing BaCO3 Curve ii represents addition of NaNO3 to a solution containing B CO Curve iii represents addition of HNO3 to a solution containing BaCO

Combustion of butane C4H10 the main component of lighter fluid is described by the chemical equation 2 CaHio 13 0 8 CO 10 H O In a particular case 84 5 grams of butane are formed by this reaction a How many moles of butane are formed b How many moles of O are consumed

13 You take 3mL of your unknown sample and 7mL water and mix them together The diluted sample gives an absorbance of 0 432 What is the concentration of the initial unknown In other words what was the concentration of your ORIGINAL solution

The decomposition of N205 dissolved in carbontetrachloride occurs as follows N O5 Solution 2NO2 2 Solution O2 g 2 This reaction is of first order and its rate constant is 5 0 x 10 4 sec If initial concentration of N205 for this reaction is 0 50 mole litre then a What will be the initial reaction rate b What will be half life period of this reaction c What will be the concentrations of N O and NO at the end of 50 minutes after the starting of reaction in

2Cu 41 Cu l2 12 12 2Na2 S O3 2Nal Na2 S406 If 100ml of CuSO4 Solution added to excess KI requires 50ml of 0 2MNa2 S2O3 The molarity of CuSO solution 0 05 M 0 1 M 0 2 M ion the following reactions took place 0 25 M A

How many of the following reactions at equilibrium will not show change in their equilibrium constants on changing total pressure Assume temperatu as constant a N g 3H g 2NH3 g b N g O2 g 2NO g c H g Cl g 2HCl g d CS g 30 g CO g 2SO g e SO3 g NO g SO g NO g f 4NH3 g 50 g 4NO g 6H O g g H O g CO g H g CO g

Two blocks of copper having same mass m and specific heat capacity s are kept in contact and have different temperature in a closed isolated box m T T T T Which of the following statement s is are correct AS surr 0 Final temperature of system is T T ASSystem msin ATT2

CE0048 13 If 8 mole of PCI is heated in a closed vessel of 10 L capacity and 25 of it dissociates into PCI and Cl at the equilibrium then value of Kp will be equal to 1 P 30 2 P 15 3 2 3P 4 3 2P F0049

71 The electrical resistance of 0 08 M caustic soda solution is 5 x 10 when placed in a column of diameter 2 cm and length 50 cm T conductivity of the solution is Take the value of n 3 A B 300 S cm 1 300 S cm CO300 Sam D O1 300 S cm 66822

Pick out the wrong statement 1 K Cr O7 reduces ferric sulphate to ferrous sulphate 2 Iron do not form amalgam 3 Permanent magnet is made by an alloy called Alnico 4 In the Lathanides ionic radius decreases from La 3 to Lu 3

The balanced equation for a voltaic cell is as follows 2NO3 aq 8H30 aq 3Ca s 2NO g 3Ca aq 12H 0 1 In one half cell containing a graphite electrode the following conditions apply NO3 0 200 M PNO 0 100 atm pH 2 000 This is combined with a standard Ca Ca half cell Under these conditions the cell potential was measured to be 3 678 V at 25 C By calculating the value of the reaction quotient and Ecell under these conditions determine the value of the standard potential for the Ca Ca half cell

Pre Medical Chemistry 185 131 500 mL of 0 2 M acetic acid are added to 500 mL of 0 30 M sodium acetate solution If the dissociation constant of acetic acid is 1 5 x 10 5 then pH of the resulting solution is 115 0 2 9 0 3 3 0 4 40

0 x 10 10 will be 0 233 2 IL 4 430 L IE0061 in saturated solution of 10 mol L At 20 C Ag CrO is 3 0 1 M NaBr 27 IE0072 61 In which of the following the solution of AgSCN 12 3 20 will be unsaturated 20 4 0 1 M AgNO 1 Ag SCN1K 2 Aglx SCN K 3 Agl x SCN1 K 4 Ag SCN K IE0073

3 r K NO Br 4 r K NOBr 32 For a first order reaction the time required for 75 of the reaction to complete is 1 Twice that required for 50 of the reaction to complete 2 Thrice that required for 50 of the reaction to complete 3 One and half times that required for 50 of the reaction to complete 4 Equal to that required for 50 of the reaction

Q6 Calculate the lines n spectrum produced in Paschen series when electron gets De excited from 5th shel and what will be the region of the spectrum 1x2 2

Gold number of starch is 25 The amount of 0 3125xa gm of starch is required to prevent coagulation of 100 ml of gold sol adding 10 ml of 10 NaCl solution if value of a is x then find value of 10x

try ALLEN and PZ are equal then 57 If the solubility of PbBr is S g molecules per litre will be considering 100 ionisation its solubility product 2 45 3 45 4 25 K PZ K PZ is 1 25

MnO aq CIO aq MnO s C10 aq Express your answer as a net ionic equation including phases AE 2MnO4 aq 3CIO aq H O 2MnO s 3ClO aq 20H7

Sir please read the whole doubt I have tried to explain my doubt as much as I can so tha t I could get the correct explanation for it an d I hope that you will see my doubt and reso Ive it my doubt is that why tertiary alcohol i s more reactive than Primary and secondar y In the internet it was given that it is more reactive because of 3 alkyl halides and so th e carbocation formed will be stable and in p rimary and secondary alcohols carbocation won t be stable but sir this case will be valid if the mechanism is Sn1 but If the mechanis m is Sn2 then there will be no formation of c arbocation instead if the mechanism is Sn2 then Primary alcohol Will react faster due to less steric hindrance But what I think is that if there is tertiary alc ohol then it will follow Sn1 mechanism and i f there is Primary alcohol then it will follow Sn2 mechanism Then in that case we have to compare that whether sn1 will be faster o r sn2 will be faster in tertiary and Primary re spectively And then we can say whether ter tiary alcohol is more reactive or Primary alc ohol is more reactive But I don t know whet her sn1 is fast or sn2 Please tell whether I a m correct upto here or not and also that whi

or a reversible reaction having AH 20 kJ mole if activation energy for forward reaction is 100 kJ mole then activation energy of backwa eaction is A 80 kJ mole OB 120 kJ mole Oc 100 kJ mole DD 20 kJ mole

10 5 M NaOH solution at 25 C is diluted 1000 times The pH of the resultant solution will 1 3 4 Correct Answor 2 Your Answer 1 Status incorrect be equal to 8 lie between 7 and 8 lie between 6 and 7 romain unchanged

Each of the insoluble salts below are put into 0 10 M hydrochloric acid solution Do you expect their solubility to be more less or about the same as in a pure water solution lead chloride barium sulfite magnesium hydroxide More soluble than in pure water Similar solubility as in pure water Less soluble than in pure water

A certain vitamin extracted from plant sources has carbon and hydrogen in 8 1 mass ratio The percentage of oxygen is nearly 7 3 The compound gave no test for nitrogen or sulphur or any other element What should be the empirical formula of the compound A C30H4502 B C15H230 C C29H4503 D C 0H150

101 Using the Gibbs energy change AG 63 3 kJ for the following reaction 2 Ag CO3 s 2Ag aq CO3 3 aq the Ksp of Ag CO3 s in water at 25 C is R 8 314 J K mol a 3 2 x 10 26 c 2 9 10 3 Syd b 8 0 x 10 2 gnibivib ya d 7 9 x 10 2 2014

o 73 View in English When a quantity of electricity equal to that required to liberate 2 24 L of hydrogen at STP from 0 1 M aqueous H SO4 is passed then the mass of copper that will be deposited at cathode in electrolysis of 02 M solution of copper sulphate will bo At mass of Cu 63 5 1 4 orrect Answer 3 tatus unattempted Add to Bookmark List 159 g 3 18 g 6 35 g 12 70 g Full Paper 20 Q No Question Status Marks Time Solution

Inate 20 When a graph between log k and 1 T is drawn a straight line is obtained The points at which the line cuts y axis and x axis respectively correspond to the temperatures 1 0 E 2 303R logA 3 0 logA 2 E R in A 4 log A

ons continued 11 What is the oxygen binding capacity of hemoglobin in a blood sample that is 100 saturated with O and has a total hemoglobin value of 12 g dL a 17 mL O dL b 4 mL O dL c 8 mL O dL d 34 ml Old 513 pix Thr

5 A crystalline solid is made up of A B and C elements Atoms of A form fcc packing atoms of B occupy octahedral voids while atoms of C occupy tetrahedral voids Select the simplest formula if atoms are missing from one of the body diagonal 1 ABC 3 A5B4C8 2 AgB4C5 4 A BC 42 I t th e th fo 1 3

What is the function of unmodified silica in SPE Select one O A To retain nonpolar species from aqueous solution B To retain polar species from organic matrices C To retain non polar species from aqueous solution D To retain polar and nonpolar species from organic matrices O E To retain polar species from aqueous solution

To an evacuated vessel with movable piston under external pressure of 1 atm 0 1 mol of He and 1 0 mol of an unknown compound vapour pressure 0 68 atm at 0 C are introduced Considering the ideal gas behaviour the total volume in litre of the gases at 0 C is close to

In human body CO combines with H O to form carbonic acid which dissociates as H CO3 H HCO3 During fear and excitation the rate of respiration increases which results the decrease in the concentration CO in blood How pH of the human blood serum is affected during such a phenomena 1 decrease 2 remains constant 3 increases ENTRE 4 change in pH cannot be determined through given information

3 0 056V 4 0 056V 55 Electrolysis of which of the following solutions w produce a solution of pH 7 2 NaOH 4 AgNO3 1 NaCl 3 KCI

c d 1 73x10 M min 3 The rate of a reaction doubles when its temperature changes from 300 K to 310 K Activation energy of such a reaction will be R 8 314 JK mol and log102 0 301 1 a 58 5 kJ mol 1 c 53 6 kJ mol 1 In the reaction b 60 5 kJ mol 1 d 48 6 kJ mol 1 DIS 22 0 03

A stone is thrown from the top of the cliff at a speed of 29 4 m s 1 in a direction 60 above the horizontal What is the time taken by the stone to return to the same level Consider g 9 8 m s A 2s B 3 s As

Consider the reactions Baeyer s reagent X MCPBA Y H O Which of the following is correct X and Y are identical X and Y are enantiomers X and Y are diastereomers X and Y are positional isomers

41g mol 27 Mass of non volatile solute molar mass 40g mol which should be dissolved in 114g octane to reduce its vapour pressure to 80 2 Points 10g 100g 20g 90g 300g of 25 solution and 400g of 40 solution by mass the

Please explain the calculation part of the question by con idering 1 Sulphur as the fixed element 2 Oxygen as the fixed element 14 Sulphur and oxygen are known to form two compounds The sulphur content in one of these is 51 while in the other is 41 Show that this data is in agreement with the law of multiple proportions Hint Ratio of oxygen in oxides of sulphur is 2 3

For the reaction CH4 Br2CH3Br HBr the experimental data require the following rate equation k CH Br HBr Br d dt CH3Br 1 k Which of the following is are true regarding this A The reaction is a single step reaction BY The reaction is 2nd order in the initial stages HBr 0 C The reaction is 2nd order in the final stages Br2 0 The molecularity of the reaction is two f

3 150 mm of Hg 4 375 mm of Hg 3 An equimolar solution of two volatile liquids A M 150 g mol and B M 200 g mol 1 has vapour pressure 500 torr If vapour pressure of pure B is 400 torr the mol fraction of component A in vapour phase is 1 0 5 3 0 3 2 0 6 4 0 4

sir how pressure in intensive property if i have 1 mole of of gas in a container then pressure be P if i leave 1 2 moles now wont the pressure become P 2 at cons volume and temperature as per PV nT

13 c 12 5 Hydrogenation of vegetable ghee at 25 C reduces pressure of H from 2 atom to 1 2 atom in 50 minute The rate of reaction in terms of molarity per second is a 1 09 x10 6 b 1 09 10 5 c 1 09 10 7 d 1 09 10 8 ut for some order of an

26 An aqueous solution of 2 non volatile solute exerts a pressure of 1 004bar at the normal boiling point of the solvent The molar mass of the solute given atmospheric pressure 1 013bar 2 Points 80g mol 61g mol 52g mol 41g mol

a Describe Frenkel defect by drawing suitable schematic diagram b Calculate the number of vacancies created when a given sample of sodium chloride is doped with 2 X 10 5 mol of aluminium chloride c Sample of KCI appears violet when it is heated in atmosphere of potassium vapours why d Zinc oxide crystal appears yellow on heating explain e What is the effect on density if a crystal is found to possess Schottky defect

Consider the hypothetical reaction and the mechanism involved at temperature T 2A 2B 2 AB Mechanism Step 1 28 Step II A B Step III AB A 2AB fast given activation energy of step II and III are E and E while activation energy for forward reaction and backward reaction of step I are E and E 1 respe If temperature of reaction is increased then rate of overall reaction decreases Select the correct statement s based on this information AB slow K Step 1 of reaction must be exothermic DIf value of Arrhenius factor A is same then at temperature T K K 1 DE E E O F F Ex 0

The rate constant for the reaction 2N O5 4NO2 0 is 2 x 10 5 sec at a given temperature If the reaction is started with 10 mole per litre of N O5 t the rate of formation of NO at the moment of the reaction when concentration of O is 2 mol litm is A 8 x 105 mol L sec B 4 8 x 104 mol L sec C 9 6 x 104 mol L sec 1 D 2 4 x 104 mol L sec

Correct statements among the following are a Commercial bleaching solution contains 3 62 mass percentage of sodium hypochlorite in water b 35 v v solution of ethylene glycol an antifreeze is used in cars for cooling the engine c 1 5 parts per million of fluoride ions in water causes the tooth to become mottled d Mass and mole fraction are independent of temperature 1 a and c 3 a b and d 2 a and b 4 a b c and d