Physical Chemistry Questions

387 An atom has four unpaired electrons The total spin of this atom will be TCO A 1 B 1 5 C 2 Which of the following statement is wrong 20 D 4

One mole of an ideal gas at 273 15 K undergoes expansion from an initial volume of 2 24 I to 22 4 against a constant pressure of 1 atm Calculate the work done 20 Also calculate ALL AH and AS

From an equimolar solution of Cl and Br ions the addition of Agt will selectively precipitates Br ion K of AgCl AgBr are 1 10 10 1 10 13 respectively sp The pH of a solution which is 0 1 M in sodium acetate and 0 01 M in acetic acid pK 4 74 would be 5 74 AgCl is less soluble in aqueous sodium chloride solution than in pure water 13 1 acts as Lewis acid In the reaction I 1 Select the correct code for above A TFTT B TTTT C FTFT D FTTT Etusion Chemistry Sheet Monic Equilibrium ENC Kund

4 1 A flask filled with CCI was weighed at a temperature and pressure The flask was then filled with oxygen at the same temperature and pressure The mass of CCl4 vapour would be about 1 Same as that of oxygen 2 1 5th as heavy as oxygen 3 5 times as heavy as oxygen Twice as heavy as oxygen 47 148

A 10 M solution of AgNO3 is made 0 2 M in NH3 Given Ag NH3 2 Ag NH3 Paragraph for Question Nos 57 to 58 Select correct options A Agtleq 10 M Ag NH3 NH3 Ag NH3 C Ag NH3 2 leq 10 M K 1 5 x 104 K 4 x 10 B Ag NH3 leq 7 5 10 M D K Ag NH3 2 6 10 8

66 Which of the following has minimum flocculation value for positively charged sol 2 A CI C PO 2 b SO d Fe CN 6

30 Non metals are usually poor conductors of heat and electricity They are non lustrous non sonorous non malleable and are coloured a Name a lustrous non metal V b Nam b Name a non metal which exists as a liquid at room temperature c The allotropic form of a non metal is a good conductor of electricity Name the allotrope d Name a non metal which is known to form the largest number of Va compounds e Name a non metal other than carbon which shows allotropy Name a non metal which is required for combustion

a 2 A balloon contains 14 0 L of air at 760 torr What will be the volume of the balloon when i taken to a depth of 10 ft in a swimming pool Assume that the temperature of the air an water are equal density Hg 13 6 g mL a 11 0 b 11 3 c 10 d 10 8

At 527 C the reaction given below has K 4 NH3 g 1 3 N 9 H 9 2 g 2 What is the K for the reaction p N g 3H g 2NH3 g 1 16 800 R 3 2 2 800R 4 2 4 None of these

8 Standard electrode potentials for Fe electrode are given Fe 2e Feils E 0 44 V E 0 77 V Fe e Fe2 brit b Fe Fe and Fe blocks are kept together then 5 a Fe decreases som b Fe increases 290 c Fe2 Fe remains unchanged d Fe decreases HT 5 sig ow I

eventh period This period corresponds to filling of electrons in the seventh energy level n 7 Like sixth period it is expected to accommodate 32 elements corresponding to filling of 16 orbitals one 7s seven 5f five 6d and three 7p However at present this period is incomplete consisting of 28 elements Last element of this period will have an atomic number of 118 and it will occupy its position in the inert gas family

For the non stoichiometric 2A B C D the following kinetic data were obtained in three different experiments measured at 298 K Initial Conc A 1 3 0 1M 0 1M 0 2M dc dt dc dt Initial Conc B K A B k A B 0 1M 0 2M 0 1M Initial rate of formation of C mol L s 1 2 10 1 2 10 2 4 10 dc 2 k A dt dc 4 K A B dt

c 21 Which of the following statements about the composition of the vapour over an ideal 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 2016 12 8 kPa toluene 3 85 kPa a Not enough information is given to make a prediction b The vapour will contain a higher percentage of benzene c The vapour will contain a higher percentage of toluene d The vapour will contain equal amounts of benzene and toluene

1 Objective type questions A Tick the correct answer 1 Which of the following does not belong to Rabi crop a wheat b paddy c legumes 2 Which can be used for both harvesting and threshing a sickle c combine b drills 3 Which helps in turning and loosening of soil a earthworm b insects 4 Compost includes a vegetable wastes b fruit peels 5 Weeds can be removed by a pesticides b weedicides D Match the following 1 Wheat 2 Maize 3 Furrow 4 Weedicides 1 Soil provides essential 2 3 4 Implement used to turn over and break up the soil is called 5 The removal of unwanted plants from the field is called 6 The sowing of seeds manually is called 7 Bee keeping is called 8 Growing of crops on rotation basis in a field is called 9 On large scale grains should be stored in c flies 1 Excessive irrigation to the crop reduces air in the soil spaces 2 Manure is decayed organic material 3 Chemical fertilisers are highly insoluble in water 4 Nitrates are the soluble salts of nitric acid 5 Repeated crop production in a soil increases its nitrogen content C Fill in the blanks 1 Chemicals II Kharif crop Ravi crop III IV Irrigation c animal dung c nitrites B Read the following statements and write True or False against them I Differentiate the following 1 Rabi and Kharif Crops emport and Green Manure d none of these to the crop fertilisers increase the nitrate content and alkalinity of the soil is an organism which damages the crop d winnow d bees and d all of these d none of these 2 Ploughing and Labelling 4 Sowing and Winnowing

The electronic configuration having maximum difference in first and second ionization energies is 1 1s 2s 2p 3s 2 1s 2s 2p 3s 3p 3 1s 2s 2p 3s 3p 4 1s 2s 2p 3s

13 Bredig arc method cannot be used to prepare colloidal solution of which of the following a Pt b Fe c Ag d Au 4 Which one is true statement

When a gas is compressed adiabatically and reversibly the final temperature is 1 Higher than the initial temperature 2 Lower than the initial temperature 3 The same as initial temperature 4 Dependent upon the rate of compression

The range of most suitable indicator which should be used for titration of X Nat 0 1M 10 ml with 0 1 M HCI should be Given kb x 10 6 B 3 5 A 2 3 C 6 8 Read the follwing statements I II carefully and select write option D 8 10

143 A cell constant is generally found by measuring the solution of aqueous solution of unni b b KC1 abam tasbure A d MgCl Prosodal conductivity of aqueous a BaCl pado gn c NaCl 065

1000 g aqueous solution of CaCO contains 10 g of calcium carbonate concentration of the solution is 1 10 ppm 3 1000 ppm 2 100 ppm 4 10 000 ppm rib sin

In two different polar molecules the ionic charge is 9 6 x 10 10 e s u and 3 2 x 10 19 coulombs respectively If inter ionic distance in both the molecules is 1A unit then the dipole moment are respectively 1 4 8 D 4 8 D 3 9 6 D 96D 2 1 D 4 8 D 4 3 33 D 4 8 D

How many unit cells are present in a cube shaped ideal crystal of NaCl of mass 1 00 g Atomic mass Na 23 C1 35 5 2 57 1021 B 128 10 1 A C D 5 14 1021 1 71x1021

For real gases the relation between P Vand Tis given by van der Waals equation P an V nb nRT where a and b are van der Waals constants nb is approximately equal to the total volume 1 of the molecules of a gas a is the measure of magnitude of intermolecular attraction i Arrange the following gases in the increasing order of b Give reason O CO2 H2 He i Arrange the following gases in the decreasing order of magnitude of a Give reason CH4 O H2

B The maximum number of orbital s that can be identified with the following quantum numbers is n 2 1 1 m 1 1 2 3 3 2 1 4 4

Equal amounts of solutions of NaOH having concentration 10 wt wt and 20 wt wt are mixed What will be molality of the NaOH in the resulting solution 1 3 0 m 3 15 m 2 0 15 m

The ratio of C 4 to C 2 in a living matter is measured to be 1 C14 C12 Activity of 12 0 gm carbon sample is 180 dpm The half life of C 4 is nearly 10 2 sec Given N 6 x 10 A 0 18 B 1 8 Mrr C 0 384 1 3 x 10 2 at the present time D 648 rith

Based on the cell representation for a spontaneous reaction at the anode Ag s AgCl s C1 aq Br aq Br l C s AgCl becomes reduced 2 Ag becomes oxidized 3 Br becomes oxidized reduced

4 moles of electrons were transferred from anode to cathode in an experiment on electrolysis of water The total volume of the pure gases at STP produced will be approximately 1 22 4 L 3 56 2 L 2 94 8 L 4 67 2 L

a How Planck s quantum theory is able to explain the phenomenon of black body radiation b The wavelength of the first line in Balmer series is 656 nm Calculate the wavelength of the second line in Ralmer series

100 mL of 0 1N I oxidizes Na S O in 50 ml solution to Na S O The normality of this hypo soluti against KMnO which oxidizes it to Na SO would be A 0 1 B 0 2 C 1 0 D 16

66 Which of the following expression for entropy change of an irreversible process dq du d ds T a ds dq T b ds dq T c ds

Color ealing Brush tool is used to The Patch tool repairs an area with pixels copi The Dodge tool is used to lighten dark areas The Clone stamp tool paints one part of an image over another part of another part of any open document that has the same colour mode The Blur tool is used to selectively blur areas of an image 4 Choose the correct answer 1 The a Clone stamp c Pattern stamp Exercise image o tool is used to remove old marks from an image b Healing brush d All of these

Which one of the following set of phenomenon would increase on raising the temperature a diffusion evaporation compression of gases b evaporation compression of gases c evaporation diffusion expansion of gases d evaporation solubility diffusion compression of gases

5 Calculate the pH of a buffer solution prepared by dissolving 30g of Na CO in 500 mL of an aqueous solution containing 150 mL of 1M HCl Ka for 3 133 109 150 HCO 5 63 x 10 11 log 1 8 197 3 10 197 0 05 2 9 197 4 11 197

13 Equal volumes of two monoatomic gases A and B at same temperature and pressure are mixed The ratio of specific heats C C of the mixture will be AIPMT Mains 2012 2 1 50 1 0 83 3 33 1 1 67

2 Difference of C and C for diatomic gas is Cp and C are molar heat capacities at constant pressure and volume respectively 1 2R 3 R 2 R 2 4 4R dt 58 2R 2 B

2 In an experiment addition of 4 0 mL of 0 005 M BaCl to 16 0 mL of arsenius sulphide sol just causes complete coagulation in 2 hrs The flocculating value of the effective ion is 900 2014 Dolnoy a Cl 1 0 c Ba 1 0 70 000 b Cl 2 0 d Ba 0 5 200 0 s 2 0 s 01 000 0 A For a gas solid adsorbent system the adsorption isotherm

if reaction 4KCIO 3KCIO4 KCI d KC1O dt K KCIO d KC O4 K KCIO dt d KC1 dt K KCIO the correct relation between K K and K 1 K K K K3 2 4K 3K K

On adding 1mL solution of 10 NaCl to 10 mL 89 gold sol in presence of 0 25 g starch so that coagulation is just prevented what will be gold number of starch 1 0 25 2 2 5 3 250 4 0 025

The emf of the cell TI TI 0 0001 M Cu2 0 01M Cu is 0 83 V The emf of this cell will be increased by 1 Increasing the concentration of Cu ions 2 Decreasing the concentration of TI 3 Increasing the concentration of both 4 1 2 both

7 The energy required to remove an electron from th surface of sodium metal is 2 3 eV What is the longe wavelength of radiation with which it can sho photoelectric effect

An element A crystallises in fcc structure 200 g of this element has 4 12 x 1024 atoms The density N 144 of A is 7 2 g cm3 Calculate the edge length of the unit cell Mas of each atom 1 26 97 x 10 24 cm 3 5 x 10 12 cm 1 2 2 299 9 pm 12x10 4 2 99 cm 48 54X

4 Conc H SO is 98 by mass and has density of 1 84 g cm 3 What volume of the conc acid is required to make 5 00 litre of 0 5 M H SO4 solution 1 250 cm 2 136 cm 3 13 6 cm 4 136 L

c 3 136 A 0 5 g sample of KH PO4 is titrated with 0 1 M NaOH The volume of base required to do this is 25 0 ml The reaction is represented as H PO OH HPO2 H O The percentage purity of KH PO4 is K 39 P 31 a 68 for 25 b 34 d 51

21 Calculate the mass percentage of benzene C6H and carbon tetrachloride CCL if 22 g of benzene is dissolved in 122 g of carbon tetrachloride 22 Calculate the mole fraction of benzene in solution containing 30 by mass in carbon tetrachloride 2 3 Calculate the molarity of each of the following solutions a 30 g of Co NO3 2 6H O in 4 3 L of solution b 30 mL of 0 5 M H SO4 diluted to 500 mL 2 4 Calculate the mass of urea NH CONH required in making 2 5 kg of 0 25 molal aqueous solution 2 5 Calculate a molality b molarity and c mole fraction of KI if the density of 20 mass mass aqueous KI is 1 202 g mL

52 Compounds A B C D E and F are CH CH CHO CH C C CH3 2 CH3CH CH CH3 CH3C CH3 C CH C CH CH3 CH CH and CH C C CH respectively 3 Which of the above compounds upon ozonolysis can give aldehydes A A B D and F B A C and E C B D and E D A only

86 In the reaction 2N2O5 4NO2 O2 initia pressure is 500 atm and rate constant K is 3 38 x 10 5 sec After 10 minutes the final pressure of N2O5 is a 490 atm c 480 atm b 250 atm d 420 atm

A bubble of gas released at the bottom of a lake increases to four times its original volun when it reaches the surface Assuming that atmospheric pressure is equivalent to the presst exerted by a column of water 10 m high what is the depth of the lake a 20 m c 30 m d 40 m b 10 m

Calcium carbonate reacts with aqueous HCl to give CaCl and CO according to the reaction given below CaCO3 s 2HCl aq CaCl2 aq CO3 g H O 1 What mass of CaCl2 will be formed when 250 mL of 0 76 M HCl reacts with 1000 g of CaCO3 Name the limiting reagent Calculate the number of moles of CaCl formed in the reaction

2 2 4 4g of CO and 2 24 litre of H at STP are mixed in a container The total number of molecules present in the container will be a 6022x1023 c 2 mole b 1 2044x1023 d 6 023x10 4