Physical Chemistry Questions

For an ideal gas sample fixed amount taken in fixed volume container collision frequency z mean free path X 1 Both Z A changes with change in T ii Z changes with change in T iii A changes with change in T iv Both are independent of temperature T v Heavier gas more molecular weight exibits higher Z compared to lighter gas if collision diameter of heavier gas is mor vi Heavier gas exibits more A compared to lighter gas vii Molecular weight of gas does not have any effect of value of A Identify number of correct statements from above

The magnitude of the change in oxidising power of the MnO Mn couple is x x 10 4 V if the H concentration is decreased from 1M to 10 4M at 25 C Assume concentration of MnO4 and Mn to be same on change in H concentration The value of x is Rounded off to the nearest integer Given al 2303R7

Q 59 Through an aqueous solution of an unknown salt of metal M M 200 g mol a current of 1 93 A is passed for 50 min If 4 g of metal is produced at cathode The charge on metal ion in solution is

Which option correctly describes freezing point depression When salt is added to a mixture of ice and water salt will occupy some space in the liquid There are now fewer water particles per unit volume and the freezing point will go down Salt particles will have no effect on a solid the melting point of the ice will stay the same When salt is added to a mixture of ice and water the freezing point will increase since salt has a higher freezing point than water Salt particles will have a similar effect on the solid increasing its melting point since salt has a higher melting point than water When salt is added to a mixture of ice and water the freezing point will go down since salt has a lower freezing point than water Salt particles will have a similar effect on the solid increasing its melting point since salt has a higher melting point than water When salt is added to a mixture of ice and water salt will occupy some space in the liquid There are now fewer water particles per unit volume and the rate of freezing and melting will go down increasing the rate of melting but not the melting point

JEE MAIN 22nd July Second shift Memory Based Paper Discussion Chemist sotopes of hydrogen which emits low energy 3 particle with half life value greater than 12 years is 2 4 Tritium and Deuterium Deuterium uum Protium

VEE MAIN EVUTJuly Soon Shin memory Based Paper Discussion Chemistry Ba OH 5 x 10 mol L dissociate 100 find conc of H O AX Bolo H 5x10 M OH 2x5x15 16 M Topic name lonic Equilibrium DBa OH Ba 2OH 2 H 0 OH 15 4 llent 16 4 1 12 M H EA BY CHO

6 Which of these statements is correct regarding a immiscible mixture of benzene 2 moles and water 3 moles at 80 oC Vapor pressure of pure benzene at 80 C 760 mm Hg Vapor pressure of pure water at 80 C 355 1 mm Hg I a Based on Dalton s law the total pressure will be 1115 1 mm Hg 1 47 atm The temperature is well above the boiling point b Based on Dalton s law the total pressure will be 517 1 mm Hg 0 68 atm The temperature is well below the boiling point c Based on Roult s law the total pressure will be 517 1 mm Hg 0 68 atm The temperature is well above the boiling point d Based on Dalton s law the total pressure will be 760 mm Hg 1 atm The temperature is exactly at the boiling point e Based on Roult s law the total pressure will be 760 mm Hg 1 atm The temperature is exactly at the boiling point

226 When some amount of sodium acetate is further added to a mixture of acetic acid and sodium acetate then pH of solution 1 increses 2 decreases 3 remains same 4 none of these can be predicted from given information

1 b You are now required to grow a further 0 10micron SiO on top of the 1 6micron of SiO by dry oxidation at 1130 C How long will this take NOTE Show how you used equations to determine parameters B and B A and time t 13 marks

4 The solubility product of BaCrO is 2 4 x 10 10 M The 24 BaCro fact 2 4 x 10 M IK x 10 M ff Ba maximum concentration precipitation in a 6 x 10 1 4 x 10 7 M 2 1 2 10 0 M 3 6 10 M 4 3 10 M of Ba NO3 possible without MK CrO solution is fat 1 4 x 10 7 M 2 1 2 x 10 0 M 3 6 10 M 4 3 10 M

The solubility of gases in water as temperature increases The solubility of most solids in water as temperature increases Which of these can be used to fill the blanks and make the statement true decreases increases decreases decreases increases decreases increases increases

A binary solution is prepared with 1 mole of liquid A P 50mm and 1 mole of liq B Pg 100mm If pressure over the mixture is reduced then the pressure in mm at which last trace of liquid will disappear will be

Two or more metals or a metal and a non metal combine and By making alloy we can increase the substance Bleaching of coloured objects can be carried out by using colourless biect O and

ode List I P pH of 0 1 M aq BOH solution at 25 C K of BOH 10 Q for the reaction A aq products A 0 8 M at t 10 min A 0 4 M at t 30 min A 0 2M at t 70 min order of reaction is R Co ordination number in hexagonal packing in two dimension S 4 00 gm silver salt of an organic acid mol wt 79 gives 3 24 gm silver residue on strong heating The basicity of acid is A P 1 Q 2 R 3 S 4 C P 4 O 1 R 3 S 2 List II 1 2 2 6 3 3 4 9 B P 4 Q 1 R 2 S 3 D P 2 O 3 R 4 S 1

latch the reaction option A and B contain elementary reaction in Column 1 Reactions with half life and order given in Column ll 2 values and order Column 11 A1 2 A 155 Column l A B C k 5M 01 1M 2M Intial concentration 02 A 20 C D K 10 MB is solvent water 03 2 AB rate k A k 5s 04 A B rate klAl k 1 s1 A2 12 0 003 10 55 5 A3 11 2 0 693 5 A4 Order or pseudo order 1 A5 Order 2

Q 55 Gold crystallizes in a face centered cubic lattice If the length of the edge of the unit cell is 407 pm The density of gold assuming it to be spherical is g cm Atomic mass of gold 197 amu 3

Two solutions A and B each of 100 L was made by dissolving 4 g of NaOH and 9 8 g of H SO4 in water respectively The pH of the resultant solution obtained from mixing 40 L of solution A and 10 L of solution B is JEE Main 2020

A colorless salt A on strong heating gives a reddish brown gas B a colorless and odorle ss gas C and a solid product D The aqueou s solution of salt A on treatment with aqueo us Kl solution gives a yellow precipitate E I dentities of A B C D and E are a Pb NO3 2 NO2 02 PbO and Pb12 Lead n itrate Nitrogen dioxide oxygen Lead oxide an d Lead iodide respectively b Pbl2 NO2 02 PbO and Pb NO3 2 respec tively c PbO NO2 02 Pb NO3 2 and Pbl2 respec tively d Pb NO3 2 02 NO2 PbO and Pb12 respec

For the reaction C4H8 6 0 4 CO 4H O Select the correct statement Rate of disappearance of O is times rate of production of CO Rate of disappearance of O is 3 times rate of production of CO2 Rate of disappearance of C4H8 and O is same Rate of disappearance of O is less than rate of disappearance of C4H8

17 The frequency of radiation emitted when the electron falls from n 4 to n 1 in a hydrogen atom will be Given ionization energy of H 2 18 10 8 Jatom and h 6 626 10 4 Js a 1 54 x 10 5 S 1 b 1 03 x 10 5 S 1

7 Water density p is flowing through the uniform tube of 7 UNA T cross sectional area A with a constant speed as shown The magnitude of force exerted by the water on the curved portion of the tube is GCI Gurukripa CAREER INSTITUTE 1 3pAv 2 pav 3 ZpAv 60 fefe DTS Diamond Test Series for NEET 2021 Created by Universal Document Converter 1 3pAv 2 pAv 3 ZnAv 2 Class XIII Spartan Batch Section A 60

2 9 times 1 3 times 3 3 times 4 27 times 28 For a reaction 2A B product rate law is At a time when t 1 18 C initial concentration 1 Co 2 Ce 3 J k 4 2 0 d A dt k A concentration of the reactant is 1 3 times 3 3 times 28 2A B 34 affent for an frem WH 4341 C fr 1 fo 2 Ce 3 9 20 t 15 4 t 2 9 times 4 27 times d A dt K t al funkat m

A reactant dissociates into different products in parallel reactions as given below Reaction 1 R25 k 21 10 sec Reaction 2 2 R3T k 1 05 x 10 sec Reaction 3 nR3U ky 7 102 sec If the initial rate of disappearance of R is 0 63 atm sec when the pressure of R is 1 atm and temperature 300 K and the pre exponential factor for all three reactions is assumed to 3 sec Use In 0 21 1 56 In 0 105 2 26 In 0 07 2 66 Read Less the value of n is 4 and the initial rate of disappearance of R is same le 0 63 at R 1 atm and T 300 K then the value of ks will be Assume k and k remain unchanged 5 25 10 sec 5 25 10 4 sec1 5 25 10 sec1 6 35 x 10 10 1

3 If 60 of a first order reaction was completed in 60 minutes 50 of the same reaction would be completed approximately log 2 5 0 4 1 40 minutes 2 50 minutes 3 45 minutes

7 Which of the following arrangement will produce oxygen 57 s at anode during electrolysis 1 Dilute HLSO with Pt electrodes 2 Fused Ned with inert electrodes 3 Dilute HLSO with Cu electrodes 4 Conc aq Nad with Pt electrodes 3

2 54 For the cell process 101 Sn s Pb 2 aq Pb s Sn aq T ratio of Pb 2 to Sn 2 ion concentration spontaneity is Given EO Sn Sn 2 E 2 0 136 V 0 126 V RM 38

Select the incorrect statement among the following A The minimum energy that an electron in hydrogen atom can have is 13 6 Ev B The energy of an electron in the 2nd excited state of hydrogen atom is 1 51eV C v AE This expression is called Bohr s frequency rule h D The concept of wave number is specially used in spectroscopic analysis

A 25 x 10 m volume cylinder is filled with 1 mol of O2 gas at room temperature 300K The molecular diameter of O2 and its root mean square speed are found to be 0 3 nm and 200 m s respectively What is the average collision rate per second for an O2 molecule 1013 2 10 0 3 1012 4 1011

A patient with sepsis will have a temperature greate than 101 F a heart rate higher than 90 beats per minute and a breathing rate higher than 20 breaths per minute What is the temperature in C K C F 32 1 8 F C x 1 8 32 K C 273

Chem Section A This section contains 35 SINGLE CORRECT TYPE questions Each question has 4 choices 1 2 3 and 4 out of Which amongst the following is the most stable carbocation CH CH CH CH NH CH CH OH CH CH CH

Consider the leaching of alumina from bauxite Identify the correct statement O It involves the reduction of aluminium O CO is used as a reducing agent to reduce sodium meta aluminate to aluminium O CO being weak acid is used to reduce the pH to increase the rate of precipitation of Al OH 3 from sodium meta aluminate In place of CO2 CO can also be used

In an coffee cup calorimeter experiment sodium hydroxide 8 16 g was dissolved in water 89 9 g The initial temperature of both were 6 5 C When the sodium hydroxide is dissolved the solution reached a maximum temperature of 26 6 C The specific heat of the solution is 3 98 J g 1 0c 1 Use NaOH as the limiting reactant calculate the molar enthalpy change of the solvation of NaOH in water A Hrxn in the unit of kJ mole Answer to 3 significant figures with the required unit as stated Do not answer in scientific notation

Substances which accelerate the rate of chemical reaction and themselves remain chemically and quantitatively unchanged after the reaction are known as catalysts The catalytic activity is localized on the surface of the catalyst The mechanism involves the following five steps Not in the order 1 Occurrence of the chemical reaction on the catalyst s surface through the formation of an intermediate II Desorption of reaction products from the catalyst surface III Adsorption of reactant molecules on the surface of the catalyst IV Diffusion of reaction products away from the catalyst s surface V Diffusion of reactant to the surface of the catalyst The correct order of sequence of the above steps to carry out a catalytic process should be V III 1 IV II V III 1 11 IV III V 1 IV II III 1 11 IV

the reaction 6C0313H O 5Br BrO 6HCO Bromine is oxidized and carbonate is reduced Bromine is oxidized and water is reduced Bromine is both oxidized and reduced Bromine is neither oxidized nor reduced A B C D Solm oxidation 2 3B 6C0 3H 0 ON 0 4 Reduction 1 5 5 Br Broz 6HC0 x 2x3 1 21 5

2 53 The reaction SO Cl g SO g Cl g is a first order gas reaction with k 2 2 x 105 sec at 320 C The percentage 1 of SO Cl is decomposed on heatng this gas for 90 min is

latch Column 1 with Column II Column l contains half life expression and Column Il contains corresponding order s rate constant expression a is the initial conc of reactant x is the concentration of product at any time t and k is the rate constant Column l 21 1 Q2 Q3 11 Q4 72 I 0 586 0 693 19 a Column II A1 k A2 A3 k a a x A4 k 2 303 log A A5 K

1 Following solutions at the same temperature will be isotonic 3 42 g of cane sugar in one litre water and 0 18 g of glucose in one litre water 2 3 4 3 42 g of cane sugar in one litre water and 0 18 g of glucose in 0 1 litre water 3 42 g of cane sugar in one litre water and 0 585 g of NaCl in one litre water 3 42 g 3 42 g of cane sugar in one litre water and 1 17 g of NaCl in one litre water

a oxidation In the context of redox reactions the removal of hydrogen from a substance is known as a oxidation b dehydration d hydrogenation c reduction 17 During rainy season power supply to our home from the electric pole will be interrupted due to forma tion of metallic oxide layer on the electric wire This is b reduction a oxidation type of reaction c redox gas c hydrogen 18 For the preservation of chips packets are filled with a oxygen b carbon dioxide act statement from the following d None d nitrogen d home from the electric pole will be interrupted due to

On the basis of following graph P V graph choose the correct statement A Total work done W q B The entropy change for the overall process is zero C For the overall process AH AU D Total work 620 77 J 1 0 P atm 0 5 A B C 20 40 Volume lit

nd the partial pressure in bar at 293K exerted by N gas over a saturated solution of 1 68mg of N dissolved in 900ml of water Given that Henry s law constant N at 293K is 78 kbar and density of water 1gm mL If the partial pressure is x x 10 bar Give x

A g B g Column l contains the order of a reaction which a reaction can follow and Column Il contains the graph which can relate with any of the following proper i Rate v s time ii t50 v s A o iii A v s time Column l Q1 1st order 02 2nd order 03 Zero order Q4 Pseudo first order Column Il A1 A2 A3 A4 A5

Sir NCERT kay in 2 paragraph mai jo kuch bhi likha hai ple ase is ko pen paper mai sequence mai likh kr samjha dijiye bcz NCERT ki language mujhe bilkul samjh nhi aa rhi Naturally the resultant reaction will take place when the right hand side in equation 6 30 is negative In A G vs T plot representing the change Fe FeO in Fig 6 6 goes upward and that representing the change C CO C CO goes downward They cross each other at about 1073K At temperatures above 1073K approx the C CO line is below the Fe FeO line AGIA G So above 1073 K in the range of temprature 900 1500 K coke will reduce FeO and will itself be oxidised to CO Let us try to understand this through Fig 6 6 approximate values of AG are given At about 1673K 1400 C 4G value for the reaction Chemistry 150 Around 1400 C 2FeO 2Fe 0 2C 0 200 2FeO 2C 2Fe 200 FeO C Fe CO 1 AG 341kJ mol AG 447kJ mol AG 106kJ mol AG 53kJ mol 2Fe 0 2FeO C O CO 2FeO 2Fe O is 341 kJmol because it is reverse of Fe FeO change and for the reaction 2C 0 2CO 4G is 447 kJmol If we calculate 4 G value for overall reaction 6 27 the value will be 53 kJmol Therefore reaction 6 27 becomes feasible In a similar way the reduction of Fe O and Fe O by CO at relatively lower temperatures can be explained on the basis of lower lying points of intersection of their curves with the CO CO curve

4 6 25 10 atm 3 Match List I and List II List I a The limits of pH values of buffer solution b Concentration of H 0 in 0 001 M Ba OH c The buffer capacity of a soultion is maximum when concentration of salt to that of acid is d Ionic product of water is A B C 1 iv 2 Iv 3 1 List II 1 5 10 2 11 Equal i 10 4 iv pka 1 D 11 4 6 25 10 atm 43 111 w gew I a was first pH b 0 001 M Ba OH H O C for t A 1 iv 2 Iv 3 1 B il

5 Concider the reaction AO BO CO D if AD B if unfavorable with 5 kcal mol and C D is favorable 8 kcal mol 1 The reaction forward is driven by 3 kcal mol 2 The reaction forward is driven by 11kcal mol 3 The reaction forward is driven by 8 kcal mol 4 The reaction forward is driven by 3 kcal mol

Questions 1 2 refer to the following information A survey was conducted among a randomly chosen sample of people who owned a cell phone in 2013 The following table shows a summary of the survey results 15 to 29 year olds 30 to 44 year olds 45 to 59 year olds 60 year olds and over Total Owned a Smart Phone Did Not Own a Smart Phone No Response Total 28 542 58 881 19 116 24 308 66 838 33 116 11 960 39 914 1 023 3 782 74 641 169 415 21 405 1 897 66 726 11 223 9 414 6 549 862 28 048 1 According to the survey results for which age group did the greatest percentage of people report that they owned a Smart Phone A 15 to 29 year olds B 30 to 44 year olds C 45 to 59 year olds D 60 year olds and over 2 Of the 15 to 29 year olds who reported owning a Smart Phone 500 people were selected at random to do a follow up survey in which they were asked whether they watched streaming videos on th There were 302 people in this follow up survey who responded Yes to the question and 198 who responded No Using the data from both the follow up survey and the initial survey which of the followin the likely to be an accurate statement A About 45 083 people 15 to 29 years old would report watching streaming videos on their Smart Phones B About 35 564 people 15 to 29 years old would report watching streaming videos on their Smart Phones C About 17 239 people 15 to 29 years old would report watching streaming videos on their Smart Phones D About 102 327 people 15 to 29 years old would report watching streaming videos on their Smart Phones

When the MnO reacts with HCl the chlorine gas is evolved according to the equation MnO 4HCI MnCl Cl 2H O Which are correct regarding this equation 1h factor of HCI is 0 5 Equivalent mass of HCI will be equal to molecular mass of HCI Equivalent mass of MnO is half of its molecular mass 4 It is redox reaction

Match the transformations in column I with appropriate options in column II Column I Column II A CO s CO g B CaCO s CaO s CO 9 3 C 2H H g D P white solid P red solid p phase transition q allotropic change r AH is positive s AS is positive t AS is negative 2011 ntholny of formation at 298 K is

The dispersion medium of colloidal solution of iron III oxide and colloidal gold is negatively and positively charged respectively Identify the correct statement s Electrophoresis can cause coagulation in both the sols Mixing of both the sols will cause coagulation Less amount of sodium sulphate is required for coagulation of gold solution as compared to that required for coagulation of iron III oxide sol Calcium chloride solution coagulates the gold solution more readily than the Fe OH 3 sol

Write IUPAC name of the given compound Solution The locant in this molecule is given as 2 9 CH CH CH CH CH C CH CH CH CH CH CH CH CH CH CH CH 3 CH 21 CH CH CH3 TT 8 7 6 CH CH C CH CH 51 CH CH CH CH CH CH CH CH CH The IUPAC name of the compound is given as CH 4 3 2

154 180 1 DIBAL H ii H O CH CH CH CH CH CN Major product formed in the given reaction is CH CH2 CH2 CH CH2 CH NH CH CH2 CH2 CH CH CHO CH CH CH CH2 CH CHO CH CH CH CH CH CH NH