Physical Chemistry Questions

organic acid Molecular mass 90 reacts with excess of silver nitrate to form a precipitate of mass 15 2 g of its silver salt On heating this precipitate 10 8 g residue is obtained The basicity of the organic acid is Ag 3

action If the standard electrode potential of Cu Cu electrode is 0 34 V what is the electrode potential of 0 1 M 2 Equilibrium constant 4 All of these 8 concentration of Cu 1 3 99 V 2 0 3105 V 3 0 222 V If Cu Cu electrode is diluted 100 times then the change in emf is 4 0 176 V

09 A number is chosen from all numbers of digits can be made with the digits 0 1 2 3 4 5 Probability that the number is divisible by 3 is digits being unrepeated in the same number 1 23 A 25 4 None of these

This quantum number is designated by the symbol m To explain splitting of a single spectral line into a number of closely spaced lines in the presence of magnetic field Zeeman effect Linde proposed that electron producing a single line has several possible space orientations for the same angular momentum vector in a magnetic field i e under the influence of magnetic field each subshell is further sub divided into orbitals Magnetic quantum number describes the orientation or distribution of electron cloud For each value of l the magnetic quantum number m may assume all integral values from to including zero i e total 27 1 values

3 A mixture of benzene and toluene contains 30 by mass of toluene At 30 C vapour pressure of pure toluene is 36 7 mm Hg and that of pure benzene is 118 2 mm Hg Assuming that the two liquids form ideal solutions calculate the total pressure and partial pressure of each constituent above the solution at 30 C 867 mm D 065 www

The vapour pressure of a solution containing 2 moles of a solute in 2 moles of water vapour pressure of pure water 24 mm Hg is a 24 mm Hg c 48 mm Hg b 32 mm Hg A 12 mm Hg iv

From the following reaction sequence CaC2 H2O CaO C2H2 C H H C H4 nC H4 C H4 n Calculate the maximum mass of polythene in kg which can be obtained from 32 kg of Calcium carbide CaC2 if overall yield of reaction

The molar conductivities of ADAC and AC are given at 25 C To calculate ADAC molar conductivity of other electrolyte required i O ANaci O ANaOH O A 0

If Ka Ka Ka values for H PO4 are 103 108 and 10 2 respectively then what is the pH of an aqueous solution containing equimolar mixture of Na HPO4 and Na3PO4 Your answer

Mole fraction of a component A in vapour phase is X and the mole fraction of component A in liquid mixture is X2 then P P are vapour pressure of pure A B The tota vapour pressure of liquid mixture is a D 0

3 JAY V 2751 51 The number of angular nodes in 3d orbital is 2 2 1 1 3 0 4 3 52 In the reaction 2NaOH H PO Na HPO 2H O the equivalent mass of H PO is

Which of the following are correct Clear Respons H Ne 0 F SO order of rate of diffusion at same T and P lg H lg He lg CH 1g0 total K E at same T U average Umpv value of velocities U rms order of N 0 0 SO order of average K E

7 10 pt A pure metal has an FCC crystal structure If the angle of diffraction for the 3 set of planes occurs at 20 62 5 first order reflection when monochromatic x ray having a wavelength of 0 1354 nm is used What is the atomic radius of this metal

ICI has 5 CI 1 Cl bond angles 90 and it has octahedral arrangement of bonding and non bonding electrons with lone pairs of central atom cis to each other SC and I are non linear and iso structural Maximum number of T bonds present in same plane in C3 S2 molecule is two B H6 Al2 CH3 6 polymeric BeH contain 3 centre 2electron bond

Clear Respon PV 1 If nRT the gases show negative deviation J PV 1 If nRT the gases are less compressible than expected from ideal behavior H and He always shows positive deviation Pb

3 A gas at a pressure of 5 atm is heated from 0 to 1 546 C and simultaneously compressed to rd of 3 its original volume Hence final pressure is 1 10 atm 2 45 atm 3 30 atm 4 5 atm

Ultraviolet light of wavelength 280 nm is used in an experiment of photoelectric effect with lithium w 2 5 eV cathode Find a Maximum K E b Stopping potential The there hold frequency for a motalic 6 x 1014 1 O

The ionisation energy of second electron in helium atom is A 100eV B 27 2eV C 13 6eV D 54 4eV heyl am confused from this question mujhe pata hai electron ko remove karane ke liye ionisation energy 54 4 ev di jaayegi but I am confused whe he ask of 2nd electron ionisation energy in helium mujhe janna tha ki ionisation energy of 1st electron and 2 electron me difference hai kya kuch

No 13 Among the following linear combination of atomic orbitals the CORREC representation of the lowest unoccupied a molecular orbital of butadiene is y 0 372 1 0 602 2 0 602 3 0 372 64 Y 0 602 10 372 2 0 372 0 602 P 0 602 1 0 372 02 0 372 3 0 602 Y 0 372 1 0 602 2 0 602 03 0 372 4

18 The specific conductivity of N 10 KCI solution at 20 C is 0 0212 ohm 1 cm 1 and the resistance of the cell containing this solution at 20 C is 55 ohm The cell constant is ON 2 1 166 cm 1 4 3 324 cm 10 1 4 616 cm 1 3 2 173 cm 1

A gas is flowing through an isentropic nozzle The gas enters the nozzle at 7 MPa and 450 and exits at 1 MPa The gas has been found to follow the truncated virial equation An expression for the second virial coefficient is B T 4 992 x 10 673 0 00743 7 3 96599 T 776 807 where T is in K The heat capacity of the gas follows the equation Cp A BT CT DT where A 1 98 x 10 B 7 344 x 102 C 5 602 x 105 D 1 715 x 10 8 1 At what temperature does the gas exit the nozzle 2 What is the gas velocity at the exit of the nozzle

The molecular weight of O and SO are 32 and 64 respectively At 15 C and 150 mmHg pressure 9 256 litre of O contains N molecules The number of molecules in two litres of SO2 under the same

When two half cell of electrode potential of Ea and Eb are combined to form a cell of electrode potential E then If na n and n are no of electron exchange in 1st 2nd and combined half cell A E Eb Ea B E a En En n En E n 12 C E n D E Ea Eb

Given that 1312 8 E 3 m Fe 8 2 m so 68 ohm 1 cm mol and 80 ohm cm mol 1 ea Fe2 SO4 3 eq What will be e 148 ohm cm eq 880 ohm cm eq 364 ohm 1 cm eq 130 ohm cm eq

The statement which is not correct about pe troleum 1 petroleum is a kind of fossil fuel s 2 petroleum is accumulated beneath sed imentary rocks 3 petroleum is called petro I for short 4 various types of liquid fuels ar e made from petroleum

At 100 K temperature A g is 50 dissociated into B g and C g as per the reaction A g B g C g at 1 atm pressure The Gibbs energy change at t temperature is Options 100 RIn3 100 RIn3 330 3 Rin

45 If the colour changes in an acid base indicator pKindicator 7 2 are as given below which of the following is correct HIn aq A B C D Yellow H aq In aq Pink In a strong alkaline solution pink colour will be observed In a strong acidic solution pink colour is observed In a strong alkaline solution yellow colour is observed At pH 5 5 In is more than HIn

A sample of crystalline soda with a mass 2 574 gm was allowed to react with an excess of hydrochloric acid and 204 3 cm of gas was liberated at 1 bar pressure and 0 C What is the number of water of crystal molecules in one molecule of soda

For a first order reaction AB the rate of reaction is 4x 10 mol L s when 4 2x 10 2 mol L What will be the value of rate constant when A is increased to 4 x 10 2 mol L 1 1 1 x 10 2 s 3 4 x 10 s 2 2 10 S 4 4 x 10 4 s

The vapour pressure of solution at give n temperature contain 72 gram of solut e in thousand gram of water is 600 4 5 Newton per metre square while that of pure water is 614 point 8 Newton per m etre square at the same temperature ca Iculate the molar weight of solute

In a parallel chemical reaction A reactant change into products B C and D by using following stoichiometry and 1st order chemical kinetics what will be the overall rate of disappearance of A A B 2A C 3A 3 D Where K K2 and K3 are first order rate constants respectively A D d A dt B 3 A dt C 1 K K K A d A dt d A dt K A K A K A K A KIA K A K 2K 3K A

When a system is taken from A to C through path ABC 10 J of heat flows to the system and 4 J of work is done by the system B C A D How much heat flows into the system in path ADC if the work done by the system is 3 1

When electromagnetic radiation of wave nature is considered an atom is emitted light continuously and Maxwell thought that electron has stationary like Thomson But in reality electron emit light continuously when it moves with velocity if also wave nature of electromagnetic radiation we

Equal masses of H2 O O and and methane have been taken in a container of volume V at temperature 27 C in identical conditions The ratio of the volumes of gases H O methane would be a 8 16 1 b 16 8 1 d 8 1 2 c 16 1 2 2014

n 12 gm of mono basic organic acid 4 8 gm carbon 0 8 gm hydrogen and 6 4 gm oxygen present 0 8 gm of silver salt of same monobasic organic acid left a residue of 0 5175 gm of silver on ignition Molecular formula of acid is O CH

5 Saturated solution of KNO3 is used to make salt bridge because 1 Velocity of K is greater than that of NO 2 Velocity of NO is greater than that of K 3 Velocity of K and NO3 are nearly same 4 KNO3 is highly soluble in water

21 Which has maximum potential for the half cell reaction 2H 2e H 1 1 0 M HCI 3 Pure water 2 Consider the following 2 A solution having pH 4 4 1 0 M NaOH

Q 13 A metal forms two oxides The higher oxide contains 80 metal 0 72 g of the lower oxide gave 0 8 g of higher oxide when oxidised Then the ratio of the weight of oxygen that combines with the fixed weight of the metal in the two oxides will be Choose answer 02 3 1 2 045 03 2

T C The rate constant for the decom at various temperatures are as follows 0 25 35 45 55 65 k s 7 9 x 10 7 3 5 x 10 5 1 35 x 10 4 5 0 x 10 4 1 5 x 10 3 4 9 x 10 Draw a graph and from it determine the activa tion energy of the reaction 1 5 The rate constants of a reaction at 500 K and 700 K are 0 02 s and 0 07 s respectively Calculate the values of E and A

6 00 g of NaOH are dissolved in water to make 5 00 L of solution What is the concentration of hydronium ions H O in this solution Express your answer with the appropriate units View Available Hint s H O A Value Units

Write the mass to two places beyond the decimal point of each component at the end of the reaction in the boxes on the bottom of the page Show your work Na3C6H5O7 3 CO 258 g mol 3 NaHCO3 14 39 84 0 g mol 4 00 g H3C6H5O7 9 00g 192 g mol 5 00 g 44 0 g mol 3 H O 18 0 g mol

Sulphate of metal M does not form precipitate with dil HCI but it forms black ppt P when H S gas is passed in presence of dil HCI P is insoluble in ammonium polysulfide Sulphate of metal M on reaction with small amount of NH4OH give precipitates and this become a soluble deep blue solution Q when excess of NH3 is passed Solution Q on acidification with acetic acid and then adding potassium ferrocyanide solution gave a chocolate brown precipitate R Select the correct statement Metal M belong to 4 th period of modern periodic table Precipitate P is insoluble in nitric acid IUPAC name of Q is tetraamminecopper III sulphate IUPAC name of R is copper hexacyanoferrate III

if radius of Zn2 is a and that of S2 is b then body diago nal of CCP lattice ZnS will be 4 a b 2 a b root3 a b root3 a b 2 some say first option some say last option please clarify

1 In a reaction X Y product if concentration of X is increased to three times then rate increases by a factor of 3 and when the concentrations of both the reactants X and Y are tripled then rate increases by a factor of 9 The rate law for the reaction can be written as O Rate K X Y O Rate K X Y O Rate K X Y O Rate K X Y1

2 5 mole of KCl is added to one Kg of water at 1 atm At what temperature in kelvin unit will the water boil of the degree of dissociation of KCl is 0 8 Kb of H O 0 52 K kg mol Give answer in nearest integer value

Given the numbers 161 cm 0 161 cm 0 0161 cm The number of significant figures for the three numbers is a 3 3 and 4 respectively b 3 4 and 4 respectively c 3 4 and 5 respectively d 3 3 and3 respectively 1998

chemical behaviour of the first member of a group of elements in the s and p blocks compared to that of the subsequent members in the same group The anomalous behaviour is attributed to their small size large charge radius ratio and high electronegativity of the elements In addition the first member of group has only four valence orbitals 2s and 2p available for bonding whereas the second member of the groups have nine valence orbitals 3s 3p 3d As a consequence of this the maximum covalency of the first member of each group is 4 e g boron can only form B 88 Al 143 BF4 whereas the other members of the groups can expand their valence shell to accommodate more than four pairs of electrons e g aluminium AlF forms Furthermore the first member of p block elements displays greater ability to form p P multiple bonds to itself e g C C C C N N N N and to other second period elements e g C O C N C N N O compared to subsequent members of the same group

50 E values of Mg2 Mg Zn Zn and Fe Fe are 2 37 V 0 76 V and 0 44 V respectively Which of the following is correct 1 Mg2 oxidises Fe 3 Zn reduces Mg2 2 Zn oxidises Fe2 4 Zn reduces Fe

The decomposition of N O5 in CCl at 318K has been studied by monitoring the concentration of N O5 in the solution Initially the concentration of N O is 2 33 mol L and after 184 minutes it is reduced to 2 08 mol L The reaction takes place according to the equation 2 N O5 g 4 NO g O g 2 Calculate the average rate of this reaction in terms of hours minutes and seconds What is the rate of production of NO during this period

Eal 1 A B Ea 1 Sandton Hoq a 2 20 Ea 2 G H 11 modoss a step 2 is rate determining Given the activation energies E 1 120 kJ mol E 96 kJ mol a For the mechanism E a 2 196 kJ mol find E a A 154 C D for the overall reaction 2A 2B2D G H som omlet paid to C 354 B 244 3 D None of these