Physical Chemistry Questions

7 moles of a tetra atomic non linear gas A at 10 atm and T K are mixed with 6 moles of another gas B at K and 5 atm in a closed rigid vessel without energy transfer with 3 5T surroundings If final temperature of mixture was K then gas B is Assuming all modes of 6 energy are active a monoatomic b diatomic c triatomic d tetra atomic

13 A vessel has 6 g of oxygen at a pressure P and temperature 400 K A small hole is made in it sc that O leaks out How much O leaks out if the pressure is P 2 and temperature 300 K 1 5 g 3 2 g 2 4 g 4 3 g

97 of chloride ion in What is the molar concentration the solution obtained by mixing 300 mL of 3 0M NaCl and 200 mL of 4 0 M solution of BaCl 1 5 0 M 2 1 8 M 3 1 6 M 4 None of these

Explain the deviation in ionisation enthalpy of some elements from the general trend by using figure Ionisation enthalpy AH kJ mol 2500 2000 1500 1000 500 899 Be 520 Li 1402 N 2080 Ne 1681 F 3 0 1314 C 1086 B 801 T 1 2 3 4 5 6 7 8 9 10 Atomic number

Human environment is formed by human beings An ecosystem is a distinct zone within the biosphere formed by the interaction of all living organism each other and with the physical environment in which they live Human beings interact with the environment and modify it according to their needs Time to Writer A Tick the correct answer 1 The surrounding of a living thing in which it exists is termed as its a lithosphere b environment c hydrosphere 2 Ecology is the study of organisms and the environment they live in a Ecology b Abiotic environment c Biotic environment d Ecosystem 3 The mixture of gases is commonly known as a solar radiation b air c humidity 4 Which gas is essential to maintain the fertility of the soil b Carbon dioxide c Methane 2 3 4 d biosphere d none of these d Nitrogen a Oxygen 3 Fill in the blanks 1 Environment is our basic life support system Nitrogen is required to maintain the fertility of the soil Ozone blocks the harmful ultraviolet rays of the sun Ecologists study specific areas of biological activity called cosustoms

52 4 g of hydrogen are ignited with 4 g of oxygen The weight of water formed is 1 0 5 g 3 4 5 g t 2 3 5 g 4 2 5 g

IS dro number e magnitude of e electron coulomb mulomb lomb mb 27 WIN NA AVA XN N ples of electrons is Eq 9 q DXF ON 4 ular mass of H SO4 in gram is a 98 g b 98 X 1 66 X 10 24 g c 98 001 g b 98 001 X 1 66 X 10 24 Q8 Which one is more heavier 98 an Q9 The new N a 3 g atom of nitrogen b 1 5 g molecules of Oxygen 5 mol o 1 5 c 45 4 L of hydrogen at STP d 1 mole of chlorine 3 mol N na N

For a reaction AB equilibrium constant is 1 66 and Kforward 0 166 hr Calculate the time in hours when concentration of B is 80 of its equilibrium concentration Given in 25 3 20

53 If the rate constant of a reaction is 2 303 10 3 s 1 then the time required for the completion of 70 of the reaction is log 3 0 48 1 5 25 minute 2 12 31 minute 3 7 25 minute 4 8 67 minute

Statement 1 Energy emitted when an electron jump from 5 2 energy level is less than when an electron jump from 2 1 in all H like atom Statement 2 The total energy difference between 1st 2nd energy level is greater than that of any two energy level provided level 1 is not part of those two energy levels A Statement 1 is true statement 2 is true and statement 2 is correct explanation for statement 1 B Statement 1 is true statement 2 is true and statement 2 is NOT the correct explanation for statement 1 C Statement 1 is true statement 2 is false D Statement 1 is false statement 2 is true

a q is state function in isochoric process b w is state function in isobaric process c Work done by the system will be zero i adiabatic free expansion Correct among the following is are 1 a only 2 b only 3 b c 4 a b c 6

x 2 A solution of ethanol in water is 10 by volume If the solution and pure ethanol have densities of 0 9866 g cc and 0 785 g cc respectively find the per cent by weight

a 2 85 x 10 51 Which of the hydrated species can exist I H502 II H O Select alternate from a II only IV H 0 III H 30 d I II III and IV c I II and IV Which one s when dissolved in water will produce an ac b I and II

verage The total number of electrons present in 1 6 gm of methane is a 6 02 1023 b 6 02 x 1022 of methane c 6 02 x 10 1

4 Number of natural life times T required for a first order reaction to achieve 99 9 leve completion is A 2 3 C 9 2 D 0 105 B 6 9

4 Two bottles of A and B contains 1M and 1m aqueous solution d 1gmL of sulphuric acid respectively 1 A is more concentrated than B 2 B is more concentrated than A 3 Concentration of A concentration of B

All India Aakash 48 The equivalent weight of NaH PO4 in the reaction NaH PO KOH NaKHPO4 H O is Given Atomic masses Na 23 K 39 P 31 1 158 2 60 3 97 4 120

137 What is the percentage hydrolysis of NaCN in N 80 solution when the dissoelation constant for HCN in 1 3 109 and Kw IC 1 0 10 14 1 2 48 3 8 2 2 5 26 4 9 6 1

Same amount of current passed through two separate electrolytic cells containing FeCl3 and NISO4 solutions respectively if 112 g of Fe deposited in first cell then amount of Nickel deposited is molar mass of Fe 56 molar mass of Ni 59

23 A gas absorbs a photon of 355 nm and emits at two wavelengths It one of the emissions is at 680 nm the other is at 2011 1 743 Ans 2 518 3 1035 4 325 nm

Within each series properties of the elements are quite similar It is very difficult to separate them from a mixture

The mole fraction of a solute in a solution is 0 1 At 298 K molarity of this solution is the same as its molality Density of this solution at 298 K is 2 0 g cm The ratio of the molecular weights of the solute is JEE Advanced 2016 3 124 and solvent MWsolute MWsolvent

Consider the given reaction PCI g PCI g Cl g If the enthalpy change i e AH for the given reaction is x J at T K then the value of AU is 1 x 8 314 T J 3 x 8 314 T KJ NCERT Pg 167 2 x 8 314 T J 4 x 8 314 T KJ

A mixture of methane carbon monoxide Ammonia NO and oxygen The initial volume of gaseous mixture is 130 c c and volume of product gases at similar condition are 60 c c Equal volume of carbon dioxide is produced by combustion of methane and carbon monoxide Volume of O required for combustion of NH3 is 3 5 times 0 require for NO and 7 times of CO Reactions are Not balanced NH3 g O g NO g O g NO g CH g O g CO g H O 1 NO g H O 1 Select incorrect statement 1 Volume of NO and NH3 are same and 20 c c each 2 Volume of CH4 is half of NH3 3 Volume of CO is equal to methane

Which of the following statement is correct regarding with chemical equilibrium 1 Based on extent to which the reactions proceed to reach the equlibrium we may have negligible conc of reactants are left 2 Equlibrium is not static 3 Concentration of reactants and products becomes constant at equilibrium 4 All of these

20 Which is expected to show paramagnetism b SO d SiO a ClO c CO 200

How many grams of concentrated nitric acid soluta should be used to prepare 250 mL of 2 0 M HNC The concentrated acid is 70 HNO a 70 0 g conc HNO3 b 54 0 g conc HNO c 45 0 g conc HNO d 90 0 g conc HNO

On applying pressure to the equilibrium icewater which phenomenon will happen 2 More water will be formed 1 More ice will be formed 4 Water will evaporate 3 Equilibrium will not be disturbed

The elements whose atoms have three outer most shells incomplete are called 1 s block elements 2 p block elements 3 f block elements 4 d block elements

4 litres of the solution Calculate the mole percentage of CH OH and H O respectively in 60 by mass aqueous solution of CH C 1 45 8 54 2 2 54 2 45 8 3 50 50 4 60 40

grams of lead were in the paint sample Atomic mass of Pb 207 Catums of Calculate the following quantities Molar mass of oxygen gas if 64 g of oxygen in 22 4 L vessel exerts a pressure of 2 atm at 0 C Average molar mass of 20 gm mixture of CH g and He g in 11 2 L vessel exerts a pressure of

143 N g 3H g 2NH 8 Kc 100M Equilibrium constant for the decomposition of 17 grams of ammonia at same temperature is 1 10 2 0 1 3 0 01 21 2 3

What amount of substance containing 60 NaCl 37 KCI should be weighed out for analysis so that after the action of 25 ml of 0 1N AgNO solution excess of Ag is back titrated with 5 ml of NH SCN solution Given that 1 ml of NH SCN 1 1 ml of AgNO AgNO NH SCN AgSCN NH NO

Which of the following does not represent redox reactions 2 2OH CrO2 H O A Cr O72 B SO2 21 2H 1 SO H O C 2Ca OH 2Cl 2 Ca CIO 2 CaCl 2H O D Cu O NO3 H Cu NO H O

The ionization constant of ammonium hydroxide is 1 77 x 10 at 298 K Hydrolysis constant of ammonium chloride is 1 5 65 x 10 2 3 6 50 x 10 2 2 5 65 x 10 10 4 5 65 x 10 13

1 A solution of sodium sulphate contains 92 g of Nations per kilogram of water The molality of Nations in that solution in mol kg is a 16 b 4 c 132 2019 Main 9 Jan I d 8

Which salt can furnish H in its aqueous solution b Na HPO 3 a NaH PO2 c Na HPO 4 d All of these

Question 14 What is the coordination entity formed when excess of aqueous KCN is added to an aqueous solution of copper sulphate Why is it that no precipitate of copper sulphide is obtained when H S g is passed through this solution with OYCOSS KCN Cu ions are absent in the

9 A hydrogen gas electrode is made at 25 C by dipping platinum wire in aqueous HCI solution of pH 4 and by passing hydrogen gas at one atmosphere The reduction potential of the electrode at 25 C will be 1 0 118 V 3 0 059 V 2 0 236 V 4 0 118 V

0 5 molal aqueous solution of a weak acid HX is 20 ionised If K for water is 1 86 K kg mol the lowering in freezing point of the solution is 1 0 56 K 2 1 12 K 3 0 56 K 4 1 12 K

218 Sodium chloride is added to the solution after Saponification to cause the b precipitation of soap d none of these a hydrolysis of soap c sedimentation of soap Q19 Number of oxygen atoms in 8g of ozone is 6 02 1023 2 Q20 a 6 02 1023 b a Ni and Cr c b Cu and Cr 6 02 1023 3 d Stainless steel is very useful alloy in everyday life In this alloy the iron is mixed with 6 02 1023 6 c Ni and Cu d Cu and An

Which pair of elements has the same characteristic chemical properties 1 Z 13 Z 22 2 Z 3 Z 11 3 Z 4 Z 24 Z 2 Z 4 4 4

Edge length of a cubic unit cell is 400 pm Its face diagonal would be 1 600 pm 2 200 pm 3 566 pm 4 692 pm Its odge

D N g 3H If a mixture containing 3 moles of hydrogen and 1 mole of nitrogen is converted completely into ammonia the ratio of initial and final volumes at the same temperature and pressure would be A 1 2 B 2 1 C 1 3 D 3 1 constant for the synthesis 81

23 In a simple cubic lattice of anions the side length of the unit cell is 2 88 The diameter of the void in the body centre is a 1 934 c 2 108 b 0 461 d 4 988

5 The pair of compounds which cannot exist in solutic is a NaHCO3 and NaOH b Na2SO3 and NaHCO3 c Na CO3 and NaOH d NaHCO and NaCl

A sample of water has its hardness due to only CaSO4 When this water is passed through on anion exchange resin SO4 ions are replaced by OH A 25 0 mL sample of water so treated requires 21 58 mL of 10 3 M H SO4 for its titration What is the hardness of water expressed in terms of CaCO3 in ppm Assume density of water 10g m

76 The first Lyman transition in the hydrogen spectrum has AE 10 2 eV The same energy change is observed in the second Balmer transition of 80 1 Li 3 He 2 Li 4 Be

52 The chloride of metal has the formula MCI The formula of its phosphate is 1 M PO4 3 3 M PO 2 MPO4 4 M3 PO4 2

The increasing order of atomic size of Li Be B and Ne is