Physical Chemistry Questions

A 0 50 g sample containing only anhydrous FeCl3 molar mass 162 5 g mol and AlCl3 molar mass 133 5 g mol yielded 1 435 g AgCl molar mass 143 5 g mol The mass of FeCl in the sample is O 0 3126 g O 0 4157 g O 0 2345 g O 0 1567 g

A 4 406 g sample of a compound containing only C H and O was burnt in excess oxygen 8 802 g of CO and 3 604 g of H 0 were produced Determine the empirical formula of the compound using section 6 of the databooklet 2 M for calculations 1 M correct EF

Consider an irreversible reaction A B C with a rate law R c If B o were 1 mol L t s A x 10 mol L B mol L 0 2 1 10 1 1 20 1 2 1 What would be the overall order of the reaction Unknown What would be the order of the reaction with respect to A 1 What would be the order of the reaction with respect to B Unknown k A n B m 30 1 4 1

25 calories of heat is required to raise the temperature by 10 C for 0 5 mol of a unknown gas at constant volume Find mol heat capacity at constant pressure of unknown gas in calorie Given R 2 calorie mole K

collowing plots correctly the variation in rate of and rate of condensation with time for a liquid in a closed container Rate of vaporization representing evaporation A Rate B Rate C D Rate Rate Rate of condensation Time Rate of vaporization 7 Rate of condensation Time Rate of vaporization Rate of condensation Time Rate of vaporization Rate of condensation Time

1 kg of aqueous sugar solution is made by dissolving 200 g sugar in water This solution is then divided into two parts A and B in the ratio of 2 3 respectively If 20 water is evaporated from both A and B parts of the solution then choose the correct option s A Concentration of solution B 17 B C Concentration of solution A B Concentration of solution A 25

Which of the following is an incorrect statement Only One Correct Answer A A mixture of mercury and water is separated by using separating funnel B C D Fractional distillation is used to separate different components of air Drugs from blood can be separated by chromatography Crystallisation is used to purity liquids

Q23 Which of the following reactions produces hydrogen H25208 H O BaO H I OMg H O O Na O 2HCI

6 The boxes in the illustrations show tiny samples of air Assume they are at the same temperature A MEADA AO C B a List the samples in order of increasing gas pressure Explain your reasoning b Sketch a volume of air that has a pressure in between the pressures in boxes A

There are two aqueous HCI solutions kept in different vessel How much solution 2 should be added to solution I in order to make 2 5 M HCI solution 100 ml 200 ml 500 ml E2M 500 ml3 2 litre 5M 5 litre

3 cuce Which of the following is not a characteristic pro the polar liquids They have high boiling points 2 They have high heat of evaporation 3 They have low viscosity

Gases A2 B are present in two containers I II respectively at 300K separated by a narrow tube of negligible volume closed by a valve On opening the valve reaction given below attains equilibr T 2 mol A g 3 L 300 K A g B g 2AB g Kp 4 Equilibrium molar concentration of AB g is 4 mol B g 300 K

Two bulbs X and Y of equal volumes are connected through a stop cock Each bulb contained 9 6 g of dioxygen gas at 0 4 atm pressure and 300 K The first bulb X is then heated to 500 K keeping bulb Y at 300 K After removing the stop cock Final pressure in atm of gas in bulb X is

The ratio of difference between 1st and 2nd Bohr orbits energy to that between 2nd 3rd orbits energy is A B TIN THESE 1 2 1 3 C 27 5 D 5 27

The standard reduction potentials for two half cell reactions are given below Cd aq 2e Cd s E 0 40V Ag aq e Ag s E 0 80V The standard free energy change for the reaction 2Ag aq Cd s 2Ag s Cd aq is given by 115 8 KJ 115 8 KJ

2 The variation of amount of gas adsorbed per gram of adsorbent with pressure at different temperatures is given in the figure below Amount of gas adsorbed T T T3 Pressure Which of the following is the correct relation b T T T3 d T T T3 a T T T3 c T3 T T

The inversion of cane sugar proceeds with half life of 50 min at pH 5 at any concentration of sugar However if the pH 6 the half life changes to 500 min at any concentration of sugar The rate law expression for the inversion of sugar can be written as 1 r k sugar H 1 3 r k sugar H 2 4 r k sugar H r k sugar H

5 mole of each of H SO CH4 C H6 and N are kept in a container A hole was made in the container After 3 hours the partial pressure of CH4 is 0 02 tm How many gases have partial pressure greater than CH4 in the container

Molecular nitrogen can be converted into NO by the following reaction sequence N 3H 2NH3 ANH3 502 ANO 6H O Calculate the mass of NO formed from 100 g of N with excess of H and O2 Atomic mass H 1 N 14 O 16 A100 gm B 150 60 gm

Which of the following is not true about a catalyst a Mechanism of the reaction in presence and absence of catalyst could be different b Enthalpy of the reaction does not change with catalysts c Catalyst enhances both forward and backward reaction at equal rate d Catalyst participates in the reaction but not consumed in the process e Use of catalyst cannot change the order of the reaction

42 In a 1st order reaction amount of the substance left after n half lives and average life of a 1st order reaction respectively are Ao 1 A 2n k C Ao 2n 1 44 x t1 2 Q No 42 DA OB OC OD B Ao 1 n k 40 n D 1 44 x t1 2

Mixing of N and H form an ideal gas mixture at room temperature in a container For this process which of the following statements is true a AH 0 AS surrounding 0 ASsystem 0 and AG ve b AH 0 AS surrounding 0 ASsystem 0 and AG ve c AH 0 AS surrounding 0 AS system 0 and AG ve d AH 0 AS surrounding 0 ASS system 0 and AG ve e AH 0 AS surrounding 0 AS system 0 and AG ve

Example 2 4 Two solutions of ethanol marked as Xand Y have been labbled as 25 ethanol by mass and 25 ethanol by volume respectively If density of ethanol is 0 789 g mL 1 and that of solution X is 0 968 g mL then point out which solution has higher molarity

D 5 moles of SO 2 and 5 moles of O2 are allowed to react At equilibrium it was found that 60 of SO2 is used up If the pressure of the equilibrium mixture is one atmosphere the partial pressure of O is a 0 52 atm b 0 21 atm d 0 82 atm c 0 41 atm

1 For the process 3 2 AB at 298 K AG is 163 kJ mol The composition of the reaction mixture is B 1 and A 10000 Predict the direction of the reaction and the relation between reaction quotient Q and the equilibrium constant K

Outside any orbital the probability of finding the electron is zero For single electronic atom or ion the most probable distance of electron in an orbital having no radial node is n a do Z from the nucleus where a is the first Bohr s radius The average distance of electron belonging from the same orbit from the nucleus decreases with increase in the value of angular momentum quantum number for the orbital

8 Which of the following statements is not correct a La OH is less basic than Lu OH 3 3 b In lanthanide series ionic radius of Ln ions decreases c La is actually an element of transition series rather than lanthanoid series d Atomic radii of Zr and Hf are same because of lanthanoid contraction

12 1 kg of aqueous sugar solution is made by dissolving 200 g sugar in water This solution is then divided into parts A and B in the ratio of 2 3 respectively If 20 water is evaporated from both A and B parts of the solution then choose the correct option s One More Correct Answer s A Concentration of solution B 17 B 0 D Concentration of solution AB Concentration of solution A 25 Concentration of both the solutions become equal

En Zn Identify the incorrect statement from the options below for the above cell 0 76 V Zn rod IZI Salt Bridge ve 1M ZnSO soln Cu rod ve IM Cus soin A If Eext 1 1 V no flow of e or current occurs B If Eext 1 1 V Zn dissolves at anode and Cu deposits at cathode

Which of the following statements is are true Urms 0 TK is constant independent of T Uav 0 TK Wavelength of ejected photoelectron can be calculated by Ozone gas can be absorbed by alkaline pyrogallol solution DOxygen gas can be absorbed by alkaline pyrogallol solution hc where E is kinetic energy of ejected photo electr

Example 2 3 Calculate the resulting molarity of the solution that is obtained by adding 5 g of NaOH to 200 cm of M 4 NaOH solution density 1 05 g cm 3 The density of resulting solution is 1 08 g cm

3 In a system A s 2B g 3C g if the concentration of C at equilibrium is increased by factor of 2 it will cause the equilibrium concentration of B to change to a two times the original value b one half of its original value 1 c 2 2 times to the original value d times the original value 2 2

For the cell shown the measured cell potential Ecell is 0 3563 V at 25 C Pt s H g 0 721 atm H aq M Cd aq 1 00 M Cd s The balanced reduction half reactions for the cell and their respective standard reduction potential values E are 2H aq 2e H g Cd aq 2e Cd s Calculate the H concentration E 0 00 V E 0 403 V

The molar heats of fusion and vaporization of benzene are 10 9 kJ mol and 31 0 kJ mol respectively If at 1 atm benzene melts at 10 9 C and boils at 62 C Which of relation for ASfus and ASvap is true O ASfus ASvap O ASfus ASvap O ASfus ASvap O All are true

15 The half life period of the following first order reaction is C H O g CH g CO g Given that the initial pressure of C H4O2 g is 84 mm and total pressure at the end of 16 minute is 110 mi 1 30 minute 2 60 minute 3 4 3 minute 6 minute

Correct statement s for the ideal gas from the given graph is are 0 g 600K AP 7 CH g 400K O Average speed of CH4 g is higher than O g Average kinetic energy per mole of CH4 g is higher than that of O g O Fraction of molecules showing most probable speed is higher for O g Most probable speed of O2 g is higher than CH4 g

is that the same 21 Airplane takeoff from an aircraft carrier is assisted by a steam driven piston cylinder with an average pressure of 1250 kPa A 17500 kg airplane should accelerate from zero to 30 m s with 30 of the en ergy coming from the steam piston Find the needed piston displacement volume Solve Problem 5 21 but assume the steam pressure in the cylinder starts at 1000 kPa dropping linearly with volume to reach 100 kPa at the end of the process

6 Small quantities of solution of compounds TX TY and TZ are put into separate test tubes containing X Y and Z solutions TX does not react with any of these TY reacts with both X and Z TZ reacts with X The decreasing order of oxidation of the anions X Y Z is a Y Z X c Y X Z b Z X Y d X Z Y

Q 34 36 By appropriately matching the information given in th of following table Columns 1 2 and 3 contains radius ratio co ord and shape respectively Column I A 0 732 1 000 I B 0 225 0 414 II 0 414 0 732 C III D 0 1555 0 225 IV a Column II 3 4 6 8 Column III P Octahedral Q Body centered cubic Planar triangular R S Tetrahedral

5 What is the minimum volume of water required dissolve 1 g of calcium sulphate at 298 K Given For calcium sulphate Ksp 9 1 x a 3 02 L b 2 00 L d 2 43 L x 10 6 c 2 56 L

1 A bottle of dry ammonia and a bottle of dry hydrogen chloride connected through a long tube are opened simultaneously at both ends the white ammonium chloride ring first formed will be 1 At the centre of the tube 2 Near the hydrogen chloride bottle 3 Near the ammonia bottle 4 Throughout the length of the

For a reaction A P the energy of activation is 15 8 kcal at 298 K Calculate the number of activated molecules if we start with 1 mol of A considering Arhenius equation to be valid Given e 26 51 3 067 10 2 Options 1 1 031 1021 2 1 847 10 2 3 5 86 x 1023 4 3 067 x 10 2

3 Which of the following statements are correct A Each atom has at least one orbital symmetrical about the nucleus B Each orbital has at least one orbital symmetrical about the nucleus C Number of elctrons in Ne having their angular momentum equal to zero are four D Number of waves made by an electron in an orbit is equal to number of orbit No 43

a 100 mL b 20 mL c 40 mL 8 The equivalent mass of MnSO4 is half its molecular mass when it is converted to a Mn 0 3 b MnO 2 CPMT 1994 2 d MnO c MnO 4 11 of air containing 21 oxygen by volume in standard LDMT 20041

c 28 g of CaSO4 were dissolved in HCl and the solution was made upto one litre with distilled water 50 ml of above solution required 25 ml of EDTA solution on titration 50 ml of tap water consumed 35 ml of same EDTA solution EBT indicator 100 ml of this water after boiling cooling and filtering required 10 ml of EDTA solution in titration Calculate the permanent temporary and total hardness in F 2

Given that the a and b constants of the van der Waals equation for acetylene gas are 4 516 ba L mol 2 and 0 0522 L mol respectively For this gas ESTIMATE i the second and third virial coefficients at 300 K ii at what temperature the second virial coefficient to be zero

If both gases NH3 and HCI are released at the same time then white precipitate will be formed near the point shown in figure NH A B C 1 A 2 B 3 C A Procinitate will not be formed HCI

NEET 10 In Bohr s model of hydrogen atom if atomic radius of the first orbit is x then the radius of the 3rd orbit w NCERT Pg 46 will be emoped cemil S zomil 1 1 x 3 3 gem 2 3x atic on Bohr s on in

6 The intermolecular potential energy for the molecules A B C and D given below suggests that Interatomic distance pm 0 100 200 Potential Energy k mol 400 300 500 600 50 A A D has the shortest bond length Interatomic distance pm A A 100 A B 150 D B A A has the largest bond enthalpy

4 Which of the following is correct 1 For H and He z 1 and molar volume at STP is less than 22 4 L 2 For H and He z 1 and molar volume at STP is greater than 22 4 L 3 For H and He z 1 and molar volume at STP is less than 22 4 L 4 For H and He z 1 and molar volume at STP is greater than 22 4 L