Physical Chemistry Questions

Titration curves for 0 1 M solutions of three weak acids HA HA HA with ionization constants K K and K respectively with a strong base are plotted as shown in the figure Which of the following options is are true K K 2 A K C K K 12 10 PH of of 41 Volume of strong base added B pK pK D K K

For the reaction system 2NO g O2 g 2NO2 g volume is suddenly reduced to half its value by increasing the pressure on it If the reaction is of first order with respect to O and second order with respect to NO the rate of reaction will A B diminish to one fourth of its initial value diminish to one eighth of its initial value C increase to eight times of its initial value D increase to four times of its initial value

Air conditioners dry the air while they cool the air Suppose an air conditioner is used to cool a room that is 7 06 m x 11 66 m x 2 53 m when the outside temperature is 33 C At this temperature the vapor pressure of water is in grams is 37 7 torr The partial pressure of water in the air is 83 5 of the vapor pressure of water How much water removed from the air cach time the air from the room is cycled through the air conditioner mass of H O

Q1 Manish got a mixture of camphor common salt and soil from his teacher The teacher asked him to separate camphor from the mixture Which technique can Manish use to separate camphor from the mixture easily filtration sublimation O evaporation O crystallization

elevation in boiling point 10 A liquid in liquid solution is distilled the distillate is found to have same composition as the original solution it is 1 Point isotonic solution azeotropic mixture ideal solution none of the above

1 For the electron in d orbital the spin angular 73 momentum is 110110 2 How many orbitals are associated with 4th 1 3 3 h 22n 15 energy 74 d eneren in scocia a fazen ETUT 1 2 2T 2 3 3 3 21 4 2 2 41 at fura

Decomposition of A follows first order kinetics by the following equation 4A g B g 2C g If initially total pressure was 800 mm of Hg and after 10 minutes it is found to be 650 mm of Hg What is half life of A Assume only A is present initially O 10 minute O 5 minute Read More O 7 5 minute O 15 minute

For the reaction 2C F4C4F8 FANTA e tan 4 1 C F Then A B C time sec Order of reaction is 3 Half life is min if initially 1 M C F4 is take Reaction must be complex

2 In a hypothetical cubic lattice A atoms occupy the corners B atoms the face centers C atoms the body center and D atoms are present at the edge center sites If all the atoms lying on one of the diagonal planes are removed the empirical formula of the unit cell will be 1 A B4D5 3 AB4CD4 2 AB4D5 4 A B3D4

The concentration of R in the reaction RP was measured as a function of time and the following data is obtained R molar 1 0 0 75 0 40 0 10 t min 0 0 0 05 0 12 0 18 The order of the reaction is Answer 00 01 02 0 3 04 05 6 07 08

elevation constant 18 The molar mass of a non volatile solute whose 2 aqueous solution exerts a osmotic pressure of 1 004 bar at 273 K will be NCERT Pg 55 1 625 5 g mol 3 226 4 g mol vial 2 700 3 g mol 4 445 9 g mol

List I P Zero order reaction Q First order reaction R Second order reaction S Third order reaction List II 1 K 2 CH3COOC H5 NaOH 3 20 30 x 2a x 2t a a x 4 K X 5 ta OP 1 4 Q3 4 R2 S 4 O P 1 5 Q3 4 R2 3 S 4 5 OP1 2 3 Q3 R2 S 4 O P 1 5 Q3 R 2 S 4 CH3COONa C H5OH

A solid is made up of three elements P Q and R Atoms P are in ccp arrangement Q atoms occupy 12 5 of the tetrahedral sites and R atoms occupy 50 octahedral voids What is the formula of the compound 1 Q RP 3 PQR 2 QR P4 4 P Q R

3 4 6 If radius of Zn 2 is a and that of S 2 is b then body diagonal of CCP lattice ZnS will be 1 4 a b 3 3 a b 2 2 a b 4 3 a b 2

1 Compute the wavelengths for the Balmer series transitions in a hydrogen atom 3 2 all the way up to 8 2 Please write all answers in nanometers Must show all your work for at least 1 one of the transitions

The equilibrium constant K for the following reaction is 1 29 102 at 600 K COCI g CO g Cl g An equilibrium mixture of the three gases in a 1 00 L flask at 600 K contains 0 256 M COCI 5 74x10 2M CO and 5 74x102 MC What will be the concentrations of the three gases once equilibrium has been reestablished if 4 09 10 2 mol of CO g is added to the flask COCI CO Ch M M M

2 In a gaseous phase reaction A g B g 1 2 C g the increase in pressure from 100 mm to 120 mm is noticed in 5 minute The rate of disappearance of A2 in mm min is a 4 c 16 b 8 d 2

a For the reaction 3Fe A14Si5018 Fe cordierite 2Fe AlSi3012 4A12SiO3 5SiO Fe garnet sillimanite quartz AH 160 6 kJ mol AS 26 2 e u AV 164 8 cm Assuming V is not a function of T or P and that all minerals present are pure phases calculate the equilibrium for the above reaction using pure Fe end members of the cordierite and garnet solid solutions assumed to be Graph the phase diagram

Consider the following cell reaction 2Fe s O2 g 4H aq E 1 67 V 2 At Fe 10 M P 0 The cell potential at 25 C is A C 2Fe 2H O aq 1 47 V 1 87 V 0 1 atm and pH 3 B B LD IIT JEE 2011 1 77 V 1 57 V

PLS PROVIDE STEPWISE SOLUTION FOR THIS QUESTION How would the concentration of Pb2 aq ions in equilibrium with Pbl s be affected if the concentration of l aq ions were doubled Options A no change c decreased by a factor of 2 B increased by a factor of 2 D decreased by a factor of 4

At 25 C the molar conductance of 0 007 M hydrofluoric acid is 150 mho cm mol and o 500 mho cm mol The value of the dissociation constant of the acid at the given concentration at 25 C is A C 7 104 9 10 3 B D WB JEEM 2014 7 10 5 9 104

Given that 1 3 m Fe Z m 50 What will be 169 Fe2 SO4 3 eq Question Type Single Correct Type 2 68 ohm 1 cm mol 1 and 1 148 ohm 1 cm eq 1 3 80 ohm cm mol 1 4 880 ohm 1 cm eq 1 364 ohm 1 cm eq 1 130 ohm 1 cm eq 1

23 Balanced chemical equation of combustion of ethane is represented as 2 C2H6 7 02 4 CO2 6 H2O Heat Energy Which of the following holds true out of the following 1 Point O2mole of ethane on combustion gives 3 mole of water 7 mole of oxygen is sufficient for combustion of 1 mole of ethane 88g of carbondioxide is produced when 2 mole of ethane is burnt in the presence of oxygen 18 g of water is produced when 30g of ethane is burnt

41 lodine molecule dissociates into atoms after absorbing light of 4500 If one quantum of radiation is absorbed by each molecule the kinetic energy per iodine atom is given by x x 10 J in scientific notation What is the value of x yl Use h 6 6 x 10 34 Js c 3 108 ms 1 and X N 6 x 1023 bond energy of l 240 kJ mol 1 A

The boiling point of a solution is higher than the boiling point of the solvent because A the vapour pressure of the solvent is lower than that of the solution B the vapour pressure of the solvent is equal to that of the solution C the vapour pressure of the solution rises over that of the solvent D the vapour pressure of the solvent is higher than that of the solution

An aqueous solution contains 0 492 M nitrous acid Calculate the pH of the solution after the addition of 3 69x102 moles of potassium hydroxide to 225 mL of this solutio Assume that the volume does not change upon adding potassium hydroxide pH

Part B Calculate the following 1 How many atoms are in a 3 5 g sample of sodium Na 2 How many grams are in 6 53 x 1022 molecules of Alcohol C H6O 3 In number two question how many atoms of Hydrogen present in Alcohol 4 In a chemical reaction of Iron and Chlorine produce a product of Iron III Chloride Fe Cl FeCl3 Calculate the limiting reactant 5 Calculate the Molecular Weight of C8H10N 402

Ti is brown while Ti4 is colourless because A Ti4 is unaffected by the crystal field Ti2 has a 3d configuration Ti4 has a 3d configuration Ti4 cannot absorb the visible light since it is smaller than Ti

Aakash Institute 23 Henry s law constant for O and N are Ko 3 3 x 107 KN 6 6 107 Calculate ratio of ie the ratio of mole fraction Xp of O and N dissolved in water at 25 C assuming that air contains 80 N and 20 O by volume 1 0 62 2 0 92 3 0 42 4 0 5

4 6 9 A crystal is made of particle x y and z x forms f c c packing y occupies all the octahedral voides of x and z occupies all the tetrahedral voides of x If all particle along one body diagonal are removed the formula of the crystal would be 1 xyz2 2 X2YZ2 3 X Y ZE 4 M

30 In a face centered cubic arrangement of A and B atoms A atom are at the corner of the unit cell and B atoms at the face centres One of the B atoms is missing from one of the face in unit cell The simplest formula of compound is 1 AB3 3 A B5 31 The fraction of the total volum 2 AgB5 4 AB 2 5

40ml of minture of G H1 2 and co is mined with 100 ml of 0 gas and the minture is emploded The residual gas occupied woy ml and are passed through KOH Solution the volume becomes 48 ml Find composition of original minture when these

In a Hard Water Sample MgSO4 1 2 ppm Then the permanent h water is Option 1 2 3 ppm Option 2 2 ppm Option 3 4 ppm Option 4

Match the nuclear processes given in List I with the appropriate option s in List II List l List II P a decay 1 n p ratio increases Q B decay 2 n p ratio decreases R Positron decay 3 Proton converts into neutron S 7 ray emission 4 Neutron converts into proton 5 Energy is released The correct option is OP 1 5 Q 2 4 5 R 1 3 5 S5 O P 1 4 Q 1 5 R 2 3 5 S 1 5 OP 2 3 Q2 5 R 3 5 S 1 5 OP 1 5 Q 4 5 R 2 S 1 4 5

In accordance with Bohr s model what is the quantum number that characterizes the earth s revolution around the sun in an orbit of radius 1 5 10 1 m with orbital speed Mass of earth 6 0 x 1024 kg 1 1 8 1076 2 2 3 1074 3 1 3 1076 4 2 6 1074

b Suppose you have two chunks of helium gas one at sea level and one at height z each having the same temperature and volume Assuming that they are in diffusive equilibrium show that the number of molecules in the higher chunk is N 2 N 0 e mgz kT in agreement with the result of Problem 1 16

Calculate the standard enthalpy of formation of CH OH 1 from the followin data 3 2 C graphite O g CO g AH 393 kJ mol CH OH 1 H g O g CO g 2H O 1 AH 726 kJ mol 1 O g H O l AH 286 kJ mol 2 bli

A catalyst decreases Ea from 1000 kJ to 600 kJ The temperature at which the rate of reaction with catalyst will be equal to the rate of reaction without catalys at 800 K is x Then the value of is X 10

The freezing point of a solution containing 4 8 g of a compound in 60 g of benzene is 4 48 C What is the molar mass of the compound Kf 5 1 K m freezing point of benzene 5 5 C A 100 g mol 300 g mol C B 200 g mol D 400 g mol

I saw an method in byjus video about how t o balance chemical equations through alge braic method but when I tried to solve a part icular equation i wasnt able to balance it th ose equations are H2 Cl2 HCI H2 N2 NH3 PLEASE PROVIDE A WRITTEN SOLUTION O NA PAPER WITH CALCULATION ONLY THR OUGH ALGEBRAIC METHOD

In an experiment it is found that at a constant temperature rate of adsorption of gas on solid surface follows the relation Rate surface area of solid A solid is taken in form of cube that has side length cm The total surface area of this cube is x cm and rate of adsorption of gas is r If this solid cube is divided equally into 10 2 cubes then total surface area available for adsorption becomes y cm and rat becomes r2 On the basis of above information select correct statement s x is 6 y is 6 0 x 104 6 x 104

A cubical crystal is such that the corners atoms are occupied by P atoms face centers are occupied by Q atoms alternate tetrahedral voids are occupied by R atom and edge centers are occupied by S atoms Based on this identify the correct option s If there are no defects in the crystal then the empirical formula should be PQ3R4S3 If all the atoms lying on one of the body diagonal are missing then empirical formula should be PQ4R8 3S4 If all the atoms lying on an axis passing through a face centre of connecting edge centers are missing then empirical formula should be P Q RS5 If all the atoms lying on an axis passing through body center and connecting opposite face centers are missing then empirical formula will be PQ R4S3

L 6 For a reaction involving a single reac tant and order other than one which of the following statement s is are true C concentration of reactant at time t a If fis the fraction of the reactant con centration consumed over time inter val t then log A is linearly related to log C when f 1 b A plot of C vs 1 is linear with slope proportional to n 1 c If 112 and 134 are the time intervals for 50 and 75 consumption of the reactant then 13 4 1 2 2 1 d A plot of log C vs log is linear with slone 1

Q Given the following entropy values in JK mol at 298 K and 1 atm H g 130 6 Cl g 223 0 HCl g 186 7 The entropy change in JK mol for the reaction H g Cl g 2HCl g is CBSE AIPMT 1996 a 540 3 b 727 0 c 166 9 d 19 8

A cube has x triads Y diads and Z tetrads what will be the sum of X Y Z 1 23 2 13 3 14 4 9 In cubic lattice atoms are arranged A at corners B 11

Obtain the parameters of the Lennard Jones potential from the second virial coefficient of carbon dioxide assuming that the van der Waals EOS is applicable jo U r k T 1 r dr b 3 B 2 NA 2 Explain this B integration and how to get this final coefficient 03

The Boyle temperature TB is defined as the temperature at which the properties of a rea gas coincide with those of an ideal gas in the low pressure limit The graph that shows the pressure dependence of the compression factor Z for a real gas at TB is A C N 1 0 N 1 0 0 0 Pressure bar 1000 A Pressure bar 1000 B D N 1 0 0 1 0 Pressure bar N N 0 1000 Pressure bar 1000

Solid State 74 What will be the sum of number of octahedral voids and tetrahedral void in the shaded plane if unit cell is of c c p type 1 3 3 0 2 4 4 None of these

Which of the following statements are incorrect Options 1 Hydrogen like alkali metals is electropositive 2 Like alkali metals hydrogen can show an oxidation state of 1 in its compo 3 Like alkali metals hydrogen can act as a strong reducing agent 4 Hydrogen shows an oxidation state of 1 in covalent hydrides

28 Reaction A B follows second order kinetics Doubling the concentration of A will increase the rate of formation of B by a factor of a 1 4 b 1 2 c 2 d 4 The reaction of A and B follows the equation The following data were observed A Jo 0 10 0 20 0 20 A g B g 2AB g Above given question a 25 10 B 0 10 0 10 0 20 Initial rate of appearance of AB g in Ms 2 5 x 10 5x104 10 x 104 AB at 20lt d None of these the value of rate constant for appearance of AB g is b 2 5x 10 c 1 25x102