Physical Chemistry Questions

A 1 kW radio transmitter operates at a frequency of 880 Hz How many photons per second does it emit 1 1 71 x 10 2 1 71 x 1033 3 6 02 x 1023 4 2 85 x 1026 A bulb of 40 W is producing a light of wavelength 620 nm with 80 of efficiency then the number of photons emitted by the bulb in 20 seconds are 1eV 1 6 x 10 19 J hc 12400 eV 1 2 x 10 8 2 1018 3 1021 4 2 x 10 1

55 Half life period of a first order reaction is 1386 seconds the specific rate constant of the reaction is A 5 0 x 10 2 s 1 C 0 5 x 10 S 1 B 5 0 x 10 3 s 1 D 0 5 x 10 3 S 1

If three elements X Y and Z crystallise in a ccp lattice with X atoms at the corners Y atoms at the cube centre and Z atoms at the edges the formula of the compound will be a XYZ c XYZ b XYZ d X Y Z

ART Quantum theory of light and photoelectric Effect AIR service on Vividh Bharati is transmitted on 219 m band What is its transmission frequency in Hertz 1 1 3 x 106 Hz 4 6 5 x 106 Hz 2 1 9 x 106 Hz 3 1 x 106 Hz

23 The ratio of area covered in 2nd orbit to first orbit is d 4 1 a 1 1 b 16 1 c 1 16 24 If r be the radius of first Bohr s orbit of H atom the de Broglie s wavelength of an ola

Maxwell said metal continuously absorb light or heat and emits continuously electron as light and this light is one colour but plank opposite to Maxwell plank said light is different colour because metal discontinuously absorb or emit light or heat 1 19 PM

1 The value of the spin only magnetic moment for one of the following configurations is 2 84 B M The correct one is a d in strong field ligand b d in weak field ligand c d in weak as well as in strong field ligand d 5 in strong field ligand

2 12 3 6 4 15 147 What is the electronic configuration of an element in its first excited state which is isoelectronic with O 1 Ne 3s 3p 3d 2 Ne 3s 3p 3 Ne 3s 3p 3d 4 Ne 3s 3p5 148 The quantum number of 20th electron of FeZ 26 would

8 40 of rotating molecules in higher ste is given by the No e No e ja Nye selar 0061696 20200 020064696 2020064696 202

c No change 33 If the maximum velocity and acceleration of a particle executing SHM are equal in magnitude the time period will be a 1 57 c 6 28 b Decreases d None b 3 17 d 12 56

49 eV me quantum of energy is 3 n 1 of these or H atom has wavelength er series has wavelength d 12 The ionisation energy of H atom is x J atom The wavelength of first Balmer line for He ion is 5x a C 13 An 36 2 2 2mc22222 h 22 2 2 5x 36 hc b d 5x 9 9hc 5x

6 A particle executing a simple harmonic motion has a period of 6 sec The time taken by the particle to move from the man position to half the amplitude starting from the mean position is a 3 A W N W S C S b d S 1 S

In reversible reaction AB the initial concentration of A and B are a and b in moles per litre and the equilibrium concentrations are a x and b x respectively express x in terms of K K a and b K a K b K K K a K b K K b K a K b K K d K a K b K K

4 2 55 The maximum and minimum number of electrons in Co having 2 s 1 1 7 0 2 2 5 3 5 2 4 Can t be determined in its ground state will be 4 2 55 2 5 1 7 0 2 2 5 3 5 2 4 fruita WHE

D Which of the following statements are correct for SO gas a It acts as bleaching agent in moist conditions b It has linear geometry c It s dilute solution is used as lubricant d It can be prepared by the reaction of dilute H SO with metal sulphide

The energy required to break one mole of Cl Cl bonds in Cl is 242 kJ mol The longest wavelength of light capable of breaking a single C1 Cl bond is 1 23 c 3 108 m s and NA 6 02 x 10 mol x AIEEE 2010 DUMET 2010 A 494 nm C 640 nm B D 594 nm 700 nm

According to Heisenberg s principle the product of uncertainties and velocities for an 9 1 10 31 kg is A B uncertainty in position electron of mass 22 8 x 10 m s 2 1 23 8 x 105 m s 25 8 x 10 m s 2 768 x 10 6 2 1

The uncertainties in the velocities of two particles A and B are 0 05 and 0 02 m s respectively The mass of B is five times to tha of the mass of A What is the ratio o uncertainties in their positions A 2 B 0 25 C 4 D 1 AXA AXB

For the reaction H g 1 8 2HI g the standard free energy is AG 0 The equilibrium constant K would be a K 0 c K 1 b K 1 d K 1

two simple of cot T 6 0 35 m 9 A particle performing SHM has time period path length 4 cm The displacement from mean position at which acceleration is equal to velocity is a Zero b 0 5 cm c 1 cm d 1 5 cm 2r and Oscillat

2 Photoelectric emission is observed from a metal surface with incident frequencies v v where v v If the kinetic energies of the photoelectrons emitted in the two cases are in the ratio 2 1 then the threshold frequency v of the metal is a 2v V V V 2 C b 2v V d v V a 1 33 How Peri valu a C

The velocity of particle A is 0 1m sec and that of particle B is 0 05m sec If the mass of particle B is 5 times that of particle A then the ratio of de broglie wavelength associated with particle A and B a 2 5 c 6 4 b 3 4 d 5 2

14 Photons of frequency 3 2 x 1016 Hz is used to irradiate a metal surface the maximum kinetic energy of the emitted photo electron is 3 of the energy of the 4 irradiating photon What is the threshold frequency of the metal a 2 4 x 1025 Hz c 1 6 x 10 5 Hz 5 The total number of orbitals in the principal shell of Het b 2 4 x 1016 Hz d 8 x 1015 Hz

In a zero order reaction for every 10 C rise of temperature the rate is doubled If the temperature is increased from 10 C to 100 C rate of reaction will becomes b 512 times d 128 times a 256 times c 64 times

A liquid solution is formed by mixing 10 moles of aniline with 20 moles of phenol at a temperature T If vapour pressure of pure phenol and pure aniline are 90 87 mm of Hg respectively at the temperature T then identify what could be the possible value of vapour pressure of the solution Question Type Single Correct Type 1 89 mm 2 80 mm 3 93 mm 4 90 mm

5 A river water sample assume density 1 00g mL S 0 28 g kg contains the following Ion Ca2 Mg2 Nat K HCO3 SO42 CH Concentration mg kg Calculate the molarity of each ion 42 10 18 2 132 50 15

40 Which of the following complexes exhibits the highest paramagnetic behaviour Where gly glycine en ethylenediamine and bpy bipyridyl moities At No of Ti 22 V 23 Fe 26 Co 27 AIPMT Prelims 2008 1 Ti NH 3 Fe en bny NH 12 4 Colox OHLE 2 V gly OH NH3

0 For a reaction with AH 95 kJ mol decide if the following statement is true If the statement is false choose the statement that makes it true Select the single best answer The product is favored at equilibrium Assume the entropy term is small compared to the enthalpy term O The statement is false Neither the product nor the starting material is favored at equilibrium The statement is false The equilibrium position of the reaction cannot be approximated The statement is true The statement is false The starting material is favored at equilibrium O O

151 ion Ma The number the number of electrons with m 0 s In an atom having 2K 8L 8M and 2N electrons are 1 6 3 8 2 2 4 16 of electrons in the M shell of the

b 24 eV d 216 eV wavelength of an electron moving in a s radius of the orbit is given by 2 d 2 2T 41 3 t light gives off yellow light that has a C d 4 2 1 1 2 9 Which of the following statements is are correct for electron having quantum numbers n 4 m 22 a The value of l may be 2 l b The value of may be 3 c The value of s may be 1 2 d All of these 10 in orbit angular momentum when an ol th CC F a 16 N S e 2 M

9 Which of the following statements is not correct for a nucleophile a Ammonia is a nucleophile b Nucleophiles attack low electron density sites c Nucleophiles are not electron seeking d Nucleophile is a Lewis acid

The value of rate constant for a first order is 2 303 10 sec What will be the time required 1 to reduce the concentration to concentration a 100 sec c 2303 sec 10 th of the initial b 10 sec d 23 03 sec

In spite of being an odd electron molecule ClO2 does not dimerise because a the odd electron is delocalised b the odd electron is localised on the chlorine atom c the two Cl O bonds do not have the same length d of px Px bonding in the chlorine atom

Lithium has bcc structure Its density is 530 kg m 3 and its atomic mass is 6 94 g mol Calculate the edge length of a unit cell of lithium metal 6 02 x 102 mol a 264 pm c 352 pm b 154 pm d 527 pm 2016

Consider the reaction 2N O 4NO 0 In the reaction NO is being formed at the rate of 0 0125 mol Ls What is the rate of reaction at this time a 0 0018 mol Ls b 0 0031 mol L s c 0 0041 mol Ls d 0 050 mol L s

147 What is the electronic configuration of an element in its first excited state which is isoelectronic with O 2 Ne 3s 3p4 1 Ne 3s 3p 3d 4 Ne 3s 3p5 3 Ne 3s 3p 3d 148 The quantum number of 20th electron of r

5 Over small temperature ranges heat capacities are often treated as if they were constant though they are not Over the range of 300 to 6000 K the constant pressure heat capacity for nitrogen gas can be modelled as CP m a bT cT dT e T a J K mol 26 09200 b J K mol 8 218801 x 10 3 c J K mol 1 976141 x 10 6 d J K4 mol 0 159274 x 10 How much heat is needed to heat three moles of N gas from 300 to 800 K e J K mol 0 044434 x 106 10 q 100 kJ

stion No 28 40 collodal solution of Agl is prepared by adding AgNO solution to KI solution ull m excess then the charge on the colloidal particles will be AO Positve BO Negative CO Neutral DO None of these

Identify the statement which is correct Question Type Single Correct Type 1 2 3 Milk is an example of homogeneous solution Adsorption process is entropy driven process In case of CsCl crystal 8 Cs ions occupy next nearest neighbour position to each Cs ion Aqueous solution of ethylene 4 glycol can be used as

a 1 5 c 7 8 b 3 5 d 12 7 73 Sulphuryl chloride SO Cl reacts with H O to give a mixture of H SO HCl Aqueous solution of 1 mole SO Cl will be neutralised by a 4 moles of NaOH b 2 moles of Ca OH d None of these c Both a b

When the following reaction come to equilibrium N g 2H g N H g K 7 4 1026 the equilibrium a Mostly products b Mostly reactants mixture contains c It can not be predicted d Some times reactants and sometimes products

The rate constant K of a reaction is found to be double to that of rate constant K of another reaction The relationship between corresponding activation energies of the reactions at same temperature E and E can be represented as two Question Type Single Correct Type 1 E E 2 E E 3 E E Nothing can be predict regarding comparision of

When the following reaction come to equilibrium N g 2H g NH g K 7 4 10 the equilibrium mixture contains a Mostly products b Mostly reactants c It can not be predicted d Sometimes reactants and sometimes products

The bond dissociation energies of X Y and XY are in the ratio of 1 0 5 1 AH for the formation of XY is 200 kJ mol 2018 The bond dissociation energy of X will be a 200 kJ mol b 100 kJ mol c 400 kJ mol d 800 kJ mol

9 In Arrhenius equation k Ae RI A may not be termed as rate constant 1 When 100 reactant will convert into the product 2 When the temperature becomes infinite 3 When the fraction of molecule crossing over the energy barrier becomes unity 4 At very low temperature

What type of reaction is aluminium hydroxid e to aluminium oxide A Thermal dissociation reaction b Electrolytic decomposition reaction C Thermal decomposition reaction involvi ng a change in colour

eet light gives off yellow light that has a 600 nm Then oton 12400eV A 0 A this light is 7x 10 s this light is 5 x 10 s ton is approximately 2 07 eV c avelength 310 pm is 10 Change in orbit angular momentum when an electro makes a transition corresponding to 3rd line Balmer series in Li ion is a h 2 C 2h b 3h 4h 2 2 11 An electron in a hydrogen d 2 0

a 34 c 122 4 eV d 2 The de broglie wavelength of an electron moving circular orbit is The minimum radius of the orbit is given by a 2 4 3 light gives off yellow light that E a TC b 2 C d

46 For the chemical process energies are plotted in graph Energy C a e fb Progress of reaction Which of the following is correct 1 It is the exothermic reaction AH b a 2 Threshold energy e a c 3 E Ea b A All of these

The incorrect statement s about Haber s process is are 1 Actually process is performed at high temperature and pressure Il The yield will increase by increasing temperature III Both yield and rate will increase high temperatures IV Both yield and rate will decrease at high temperatures