Gaseous and liquid states Questions and Answers

037 long cm 17 201 face 0Q 44 The total flux associated with the given cube will be where a is side of the cube EU 038 4 x 9 x 10 Sl units 2 C a 1 C 4 C 6 C 3 C S C 8 C 7 C 1 162 x 10 Nm C 2 162 x 10 Nm C 3 162 x 10 6 Nm C 4 162m x 106 Nm C ES0043 ENSENY

A ballon having weight 50 kg is filled with 685 2 kg of helium gas at 760 mm pressure and 25 C What will be its pay load if it displaces 5108 kg of air 1 4372 8 kg 2 4392 6 kg 3 4444 4 kg 4 3482 9 kg

A mixture of CO and CO2 is found to have a density 1 5g litre at 30 C and 730 mm What is the composition of the mixture 1 CO 44 CO2 56 2 CO 32 CO2 68 3 CO 70 CO2 30 4 CO 9 CO2 91

3 9650 C 16 The weight of silver At Wt 108 displaced by a quantity of electricity which displaces 5600 mL of AIPMT 2014 O2 at STP will be 1 5 4 g 3 54 0 g 2 10 8 g 4 108 0 g

According to Charle s law at constant pressure 100 ml of a given mass of a gas with 10 C rise in temperature will become 0 00366 T initial 0 degree 1 273 1 100 0366 2 99 9634 3 103 66 4 100 366

ALLEN 15 Three equal masses of 1 kg each are placed at the vertices of an equilateral triangle PQR and a mass of 2 kg is placed at the centroid O of the triangle which is at a distance of 2 m from each of the vertices of the triangle The force in newton acting on the mass of 2 kg is 1 2 2 2

258 A carnot engine working between 300 K and 600 K has work out put of 800 J per cycle The amount of heat energy supplied to the engine from source per cycle will be 1 800 J 3 1200 J 2 1600 J 4 900 J HT0282

53 The average speed at T in kelvin and the most probable speed at T2 in kelvin of CO gas is 9 0 x 104 cm s Calculate the values of T and T2 A 1682 5 K 2143 4 K B 1312 5 K 1243 4 K C 1881 5 K 2233 4 K D 1712 5 K 24 13 4 K 3

0 Consider the following reaction Zn s 2HCl aq ZnCl aq H g If 520 mL of H g is collected over water at 28 C and the atmospheric pressure is 1 atm If vapour pressure of water at 28 C is 28 3 mm Hg Then the amount of Zn in g taken at the start of the reaction is assuming all the Zn s gets converted in product molar mass of Zn is 65 g mol 1 4 13 g 2 2 14 g 3 1 32 g 4 0 10 g

54 The most probable speeds of the molecules of gas A at T K and gas B at T K are in the ratio 0 715 1 The same ratio for gas A at T K and gas B T K is 0 954 Find the ratio of molar masses MA MB 1 1 965 2 1 0666 3 1 987 4 1 466

COMP Problem 3 A swimmer coming out from a pool is covered with a film of water weighing about 18 g How much heat must be supplied to evaporate this water at 298 K Calculate the internal energy of vaporisation at 100 C Avap H for water at 373 K 40 66 kJ mol NCERT Solved Example Solution The process of evaporation is 18 g H 0 1 18 g H O g

6 In Young s double slit experiment one of the slits is so painted that intensity of light emitted from it is half of that of the light emitted from other slit Then 1 fringe system will disappear 2 bright fringes will become brighter and dark fringes will be darker 3 both bright and dark fringes will become darker 4 dark fringes will become less dark and bright fringes will become less bright W00046

Sample Problem Ammonia contains 82 35 of nitrogen and 17 65 of hydrogen Water contains 88 90 of oxygen and 11 10 of hydrogen Nitrogen trioxide contains 63 15 of oxygen and 36 85 of nitrogen Show that these data illustrate the law of reciprocal proportions

46 P 9 The mass of one litre sample of ozonised oxygen at N T P was found to be 1 5 g When 100 mil this mixture at N T P were treated with turpentine oil the volume was reduced to 90 mL Calcu the molecular mass of ozone As ozone is absorbed by turpentine oil therefore volume of ozone in 100 mL of the mixture Sol

NEET 1 2016 Which of the following statement about the composition of the vapour over an ideal a 1 1 molar mixture of benzene and toluene is correct Assume that the temperature is constant at 25 C Given Vapour Pressure Data at 25 C benzene 12 8 kPa Toluene 3 85 kPa 1 The vapour will contain a higher percentage of benzene 2 The vapour will contain a higher percentage of toluene 3 The vapour will contain equal amounts of benezene and toluene 4 Not enough information is given to make a

21 In the following figures four curves A B C D are shown the curves are Pressure Pressure Volume 1 Isothermal for A and B while adiabatic for C and D Volume 2 Isothermal for A and C while adiabatic for B and D 3 Isothermal for A and D 4 Adiabatic for A and C while isothermal for B and D

HT0234 diatomic gas at HT0241 219 A gas for which y 5 3 is heated at constant pressure The percentage of total heat given that will be used for external work is 1 40 2 30 3 60 4 20

Mole fraction of the component A in vapour phase is X and mole fraction of component A in liquid mixture is X then P vapour pressure of pure A P vapour pressure of pure B A B then total vapour pressure of the liquid mixture is 1 2 3 4 P X2 A X PX1 X PBX1 X2 PBX2 X1

HT0214 198 In a thermodynamic process pressure of a fixed mass of a gas is changed in such a manner that the gas releases 20 joules of heat and 8 joules of work was done on the gas If the initial internal energy of the gas was 30 joules then the final internal energy will be 1 2 J 2 42 J 3 18 J 4 58 J

92 Pre Medical Physics 192 Oxygen and hydrogen gases are at temperature 199 1 T Then average K E of each molecule of oxygen gas is equal to how many times of average K E of 1 st

181 If the total number of H molecules is double that of the O molecules then ratio of total kinetic energies of H to that of O at 300 K is 1 1 1 2 1 2 3 2 1 4 1 16 1

3 kl 2 HT0200 185 Which of the following statement is true according to kinetic theory of gases 4 3 k1 2 1 The collision between two molecules is inelastic and the time between two collisions is less than the time taken during the collision 2 There is a force of attraction between the molecules 3 All the molecules of a gas move with same velocity 4 The average of the distances travelled between two successive collisions is mean free path HT030

HT0206 190 22 g of CO at 27 C is mixed with 16 g of O at 37 C The temperature of the mixture is At room temperature degrees of freedom of CO 7 and degrees of freedom of O 5 1 31 16 C 2 27 C 3 37 C 4 30 C HT0207

Pre Medical Physics 91 186 Gas exerts pressure on the walls of container because the molecules 1 Are loosing their Kinetic energy 2 Are getting stuck to the walls 3 Are transferring their momentum to walls

182 At which of the following temperature any gas has average moleculer kinetic energy double that of at 20 C 1 40 C 2 80 C 3 313 C 4 586 C HT0198

HT0199 184 The kinetic energy associated with per degree of freedom of a molecule is 1 MC 3 KT 2 mma 2 KT 4 3 kT 2 HT0200

10185 170 A cylinder of 200 litre capacity is containing H 2 3 x 105 4 5x105 The total translational kinetic energy of molecules 176 is 1 52 x 10 J The pressure of H in the cylinde will be in N m 1 2 x 10 3 4 x 105 Sessi 2

HT0198 183 When temperature is increased from 0 C to 273 C what will be the ratio of final to initial the average kinetic energy of molecules 1 1 2 3 3 4 4 20 HT0199

2 3 grams of a mixture of NO2 and N2O4 have a pressure of 0 82 atm at temperature TK and volume V litres If V 1 300 calculate PNO2 Assume that all the NO2 was converted into N O4 A 0 52 atm B 0 38 atm C 0 19 atm D 0 41 atm

When 50ml of 0 015 mol L NH3 H20 solution is mixed with 100ml of 0 15 mol L MnS04 solution is there Mn OH 2 precipitation If the mixing does not produce Mn OH 2 precipitation at least how many grams of NH4 2SO4 solid should be added to the MnSO4

1 168 The average kinetic energy of a gas molecule at 27 C is 6 21 x 1021 J Its average kinetic energy at 227 C will be 1 52 2 x 102 J 2 5 22 x 10 J 3 10 35 x 102 J

158 Vm Vay and Vmp are root mean square average and most probable speeds of molecules of a gas obeying 164 Maxwell s velocity distribution Which of the following statements is correct 1 v m 2 v 3 v mp 4 v mp p mp V V av V V rms mp V V rens av

d 163 The root mean square and most probable speed of the molecules in a gas are 1 same 2 different 3 cannot say 4 depends on nature of the gas HT0179

1 The root mean square rms speed of oxygen molecules O at a certain temperature T absolute is v If the temperature is doubled and oxygen gas dissociates into atomic oxygen The rms speed 2 remains v 1 becomes v 2 3 becomes 2v 4 becomes 2v HT0177 167

nt volume e different t me HT0149 ure P and MEAN FREE PATH 142 The root mean square velocity of the molecules of an ideal gas is 1 RT M 3 3RTM 2 3RT M 4 RT 3M HT0157

A metal s volume is determined by taking the difference in volume readings of a partially filled graduated cylinder and one with the metal fully submerged The initial volume is 1 32 mL The final volume is 6 40 mL The mass is 33 46 g What is the density in g mL Give answer out to hundredths Just write the number Do not write the unit You may add an attachment to support your answer Your Answer

at pressure of e is reduce to gas taken out of gas is constant kg 139 At N T P volume of a gas is changed to one fourth volume at constant temperature then the new pressure will be 1 2 atm 3 4 atm 2 25 3 atm 4 1 atm

50 None of the above HT0167 152 The speeds of 5 molecules of a gas in arbitary units are as follows 2 3 4 5 6 The root mean square speed for these moecules is 1 2 91 2 3 52 3 4 00 4 4 24 HT0168

HT0148 VA SE M 136 In kinetic theory of gases it is assumed that molecules 1 Have same mass but can have different volume 14 2 Have same volume but masses can be different 3 Have both mass and volume different 4 Have same mass but negligible volume

146 The r m s speed of a gas molecule is 300 m s Calculate the r m s speed if the molecular weight is doubled while the temperature is halved 2 150 m s 1 300 m s 3 600 m s 4 75 m s

39 pal in a cylinder of 27 C and O 23 JK 1028 of these 138 The thermodynamic variables of a jar filled with gas A are P V and T and another jar B filled with another gas are 2P V 4 and 2T where the symbols have their usual meaning The ratio of the number of molecules of jar A to those of jar B is 1 4 1 2 2 1 3 1 2 4 1 1

132 The number of oxygen molecules in a cylinder of volume 1 m at a temperature of 27 C and pressure 13 8 Pa is Boltzmaan s constant k 1 38 x 10 23 JK 1 6 23 x 1026 2 0 33 x 1028 3 3 3 x 10 4 None of these HT0145 138 The th A are F gas an their L molect 1 4 139 At N T

its temperature 1 T will be 2 2T 3 2T 4 2 2 T HT0135 23 250 litre of an ideal gas is heated at constant pressure from 27 C such that its volume becomes 500 liters The final temperature is 1 54 C 2 300 C 3 327 C 4 600 C HT0136

3 250 K HT0143 131 The variation of PV graph with V of a fixed mass of a ideal gas at constant temperature is graphically represented as shown in figure 1 PV 3 PV V 2 PV 4 PV

HT0146 14 134 Hydrogen and helium gases of volume V at same temperature T and same pressure P are mixed to have same volume V The resulting pressure of the mixture will be 1 P 2 2 P 3 2P 4 Depending on the relative mass of the gases 14

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

ALLEN sics d inside a balloon expands 126 Relation PV RT is given for following condition n PV2 3 constant The for real gas 1 High temperature and high density 2 Low temperature and low density 2 L k balloon is 2 decreasing 4 can t be said

27 A projectile is thrown into space so as to have the maximum possible horizontal range equal to 400m Taking the point of projection as the origin the coordinates of the point where the velocity of the projectile is minimum are 1 400 100 m 2 200 100 m 3 400 2001 m

29 am 3 High temperature and low density 4 Low temperature and high density HT0139 127 A container of 5 litre has a gas at pressure of 0 8 m column of Hg This is joined to an evacuated container of 3 litre capacity The resulting pressure will be At constant temp 1 4 3 2 0 5 m 3 2 0m 4 3 4 m

124 A balloon contains 500 m of helium at 27 C and 1 atmosphere pressure The volume of the helium at 3 C temperature and 0 5 atmosphere pressure will be 1 500 m 3 900 m 2 700 m 4 1000 m 131 The va a idea repres 1 PV