Physical Chemistry Questions

Loamy soil is a mixture of clay silt and san d It is the best top soil for growing plants Which of the following statements most accurately e xplains the property of loamy soil A Holds the maximum amount of water th at enters it B Permits only a certain amoun t of water to enter it C It contains very little amount of humus D Allows water to pass through it rapidly

For the reaction 2A B 3C d B dt between K K and K3 is 1 K K K 2 2K K 3K3 K A d C dt AV 21 dt A K A the correct relation

A n type semiconductor is obtained if we dope 1 poi O Silicon with a trivalent element O Silicon with a pentavalent element OA pentavalent element with silicon O A trivalent element with silicon

Example Exercise 17 2 Calculating Oxidation Numbers for Sulfur Calculate the oxidation number for sulfur in each of the following ions a sulfide ion S b c d sulfite ion SO sulfate ion SO thiosulfate ion S 0

In the electrolysis of aq NaCl 4 moles of H ape evolved along with 0 5 moles of O Find the mass of Cl liberated CaMAIN BOARD In the electrolysis of aq NaCl 4 moles of H are evolved along with 0 5 moles of O Find the mass of Cl liberated Car MAIN BOARD lo siv of this gu on

Q8 A solution of 16 hydrochloric acid is to be diluted by adding a 1 hydrochloric acid solution to it The resulting mixture is to be more than 4 but less than 6 hydrochloric acid If we have 1280 L of the 16 solution then how many liters of the 1 solution will have to be added 5

Consider the following changes 1 kg water AH liquid at 25 C 1 kg water AH liquid at 100 C 1 kg water steam at 100 C Given Specific heat of water 1 cal g C Latent heat of vaporisation of water 10 kcal mo AH is a 75 kcal b 550 kcal c 750 kcal d 55 kcal

The equilibrium constant K for decomposition of gaseous H O H O g H g O2 g is related to degree of 2 dissociation a at a total pressure P given by 1 Kp 2 Kp 3 Kp 3 1 2 a p 1 a 2 a 2 33 2 a p 1 a 2 a the a 2p 2 1 a 2 a 3 2 1 2

What is the single particle collisional frequency at sea level with T 280 K and P 1 15 atm The corresponding single particle collision frequency is reported as 10 0 s in the CRC Handbook of Chemistry and Physics 62d ed p F 171 Express your answer in reciprocal seconds to two significant figures AEO 211 4 02 4 02 10 S 1

Concentration of A B and C vs time graph for the reaction A 2B C is given below The experimental rate law of the reaction is obtained as Rate K A Choose the correct statement s from the below given options Use In2 0 7 and In3 1 B A B C N One More Correct Answer s D Concentration mol L t 50 time sec At time t A B t 21 43 sec nearly Half life of reaction 50 sec Rate constant k In 2 50 sec 1 C A

1 The atomic masses of He and Ne are 4 and 20 amu respectively The value of the de Broglie wavelength of He gas at 73 C is M times that of the de Broglie wavelength of Ne gas at 727 C M is a 2 c 4 b 3 d 5

2 A reaction mixture containing 0 50 atm N 3 0 atm H and 0 50 atm of NH3 is heated to 725 K If the value of K at 725 K is 4 28 x 10 5 atm 2 in which direction the following reaction will go N g 3H g 2NH g

A scuba diver ascends too quickly and develops the bends A nitrogen bubble has formed in the patient s elbow At a depth of 50 ft where the pressure is 2 51 atm the bubble had a volume of 0 018 mL Assuming a constant temperature and number of moles of nitrogen in the bubble what volume did the bubble increase to at the surface where the pressure is 1 00 atm bubble volume at surface The scuba diver is placed into a hyperbaric oxygen chamber where the pressure is 3 98 atm What is the volume of this same nitrogen bubble while the patient is in the hyperbaric chamber bubble volume in chamber mL ml

Find the pH during the titration of 25 00mL of 0 150 weak acid with 0 250 M strong base solution Ka 1 08 10 5 Kb 9 25 10 10 FIND a Buffer solution b At equivalence point c At half equivalence point d 2mL to the right of Half equivalence point e 2mL to the equivalence point

For the reaction 12 g Cl g 2ICI g ArxnG 10 91 kJ mol For an initial reaction mixture which contains P12 0 114 bar PC12 0 102 bar and PICI 0 355 bar what will happen in this system System is not at equilibrium and will shift towards reactants System is not at equilibrium and will shift towards products More information is required to answer this question System is at equilibrium and thus no change will occur

0 In which of the following reactions H O is not an oxidising agent 2 1 4H O PbS4H O PbSO4 4 Mn 2OH 2 2 Mn H O 3 2FeSO4 H SO4 H O Fe SO4 2H O 4 I H O 2KOH2KI 2H O O

The concentration in the chemical solution mixing problems at anytime t is equal to O the concentration of both the incoming and outgoing solutions O the concentration of the outgoing solution O the concentration of the incoming solution none of the choices

su 6 The total number of tetrahedral and octahedral voids in 0 5 mol of a compound forming hcp structure are a 6 022 x 1023 6 3 01 x 1023 c 9 033 x 1023 d 12 044 x 1023

2 For the melting of NaCl heat required is 7 26 kcalmol and AS increases by 6 73 cal mol 1 K 1 The melting point of the salt is 2 500 K 4 1 77 C 1 805 75 C 3 1 77 K

non ionized forms of the drug novocaine in the stomach pH 1 98 and the intestine pH 8 98 if its pk 8 98 Where will the drug be absorbed in the stomach and or intestines

If 14 kg of N reacts with 15 Kg H 50 yield to form NH3 then which of the following is are correct 1 17 Kg of NH3 will be formed 2 7 Kg N will remain left 3 12 Kg of H will remain left 4 All of these

For the given reaction 2A s B g C g 2D s E s the extent of reaction of B was found to be 20 at 300 K and 24 at 500 K The rate of backward reaction a increases with increase in pressure and temperature b increases with increase in pressure and decrease in temperature c depends on temperature only and decreases with increases in temperature d depends on temperature only and increases with increase in temperature

37 The heat of neutralisation of HCI by NaOH is 55 9 kJ mole If the heat of neutralization of HCN by NaOH is 12 1 kJ mole the energy of dissociation of HCN is 1 43 8 kJ 3 68 kJ 2 43 8 kJ 4 68 kJ

Calculate the a Normality and b Molarity of sulphuric acid solution prepared by dissolving 13 3 mL of sulfuric acid in 500 mL water specific gravity for concentrated sulfuric acid is about 1 84 g mL

For the reaction 2NO g O g 2NO g Calculate G at 700 K if change in enthalpy and entropy are 113kJ mol and 145J Kmol respectively Predict the spontaneity of the reaction The enthalpy change for the transition of water to steam Hvap 40 8KJ mol at 373K Calculate the entropy change for the process hono C CH Calculat 20 360 24 O

theory of electrolyte solutions d You are given an aqueous NaCl solution of 1 0 mol kg at 25 C If you are asked to calculate the activity coefficient of the solution which theory or expression do you think would be the most suitable State the reason

A gas mixture consisting of 50 mol ethane 1 and 50 mol n butane 2 at 400 K and 5 bar enters a compressor and leaves it at 600 K and 50 bar Calculate the enthalpy change in the compression process if the system obeys Redlich Kwong equation of state

High temperature and low pressure favourable condition for the formation of product in the following reaction aA bB cC then which relation is correct 1 AH ve 2 AH ve 3 AH ve 4 AH ve a b c a b c a b c a b c

On addition of 0 25 mol of a non volatile solute HA mono basic acid in 5 mol of benzene solute gets partially dimerised an the pressure of solution measured is 581 11 mm Hg On further titration of this solution 200 mL of 1 25 M NaOH required to reach end point NaOH 1 21 g mL PBenzene 600 mm Hg PH O 23 76 mm Hg 2HA HA 2 Degree of association of solute a in solution is

MCB MCB 44214 4 I ofte beni yake to co 11000 e ka switchgear Bu 0244 RACE 15 ofte Apffe BF 1 2314 R P2 Caftro afo Fil 1 pl J r FORT 0 P H 12R J 0 1000 V A mechanical circuit breaker miniature citcuit breaker offee og ofta opi 2 NURIA ARRA OG ER OPG SPOG OKEA I OKER FOR A H H Gente 2 Ci 12 x r ARA ORICE ARKA OG PERO 27rl ok Ch 29 ART H 2 rlh Highest safe current IAR IN P25 Tabs fcc 23 fo for IC ICT OG BEG RIGA 12 pl J r 2 rlh 1 2 Jh P 10 5 A 11 faireen STA SAAR 12 4 2 15 3 4 C F FACTO AGRIC REFR 2 5 2 C C K 220 V S FACT 220 V Corte 3 1 x r 233 1 3 af FruG OR THE 1 3 I MIGE

30 g of KMnO4 sample containing inert impurity is completely reacted with 60 ml of 56 volume of H O in acidic medium then what is the 2 percentage purity of KMnO4 Molecular weight of KMnO4 158 1 35 5 2 36 8 63 2 CA FO

Consider a sealed can that is filled with 4 4 kg of water at 115 C and P 248 kPa Now a leak develops and the pressure in the can drops to the local atmospheric pressure of 100 kPa Cp 4 23 kJ kg K The vapor leaves the can as soon as it is formed How much vapour will evapourate before the liquid water reaches its boiling temperature at atmospheric pressure NB water s enthalpy of vapourisation is roughly 2257 kJ kg a 4 400 kg b 0 120 kg c 1 093 kg d 0 030 kg e 0 015 kg

The chemical formulae of some acids are listed in the first column of the table below and in the second column it says whether each acid is strong or weak Complete the table List the chemical formula of each species present at concentrations greater than about 10 6 mol L when about a tenth of a mole of the acid is dissolved in a liter of water acid HIO H CO HNO HCI strong or weak strong weak weak strong species present at 106 mol L or greater when dissolved in water X 0 0 Please explain answer and list ALL species present I will be sure to leave

If an ionic solid XY X Y are monovalent ions is doped with 10 2 mole of another ionic solid AY 31 then the concentration of the cation vacancies created is 1 6 023 1019 mol 1 2 60 23 1018 mol 1 3 12 05 x 1021 mol 1 I wt 1205 x 1020 mol 1

An ideal solution made by mixing two volatil components A and B If the vapour pressure c solution is 170 mm Hg then mole fraction of A i vapour phase is P 200 mm Hg P 100 mm Hg 1 0 72 3 0 68 2 0 82 4 0 50

Consider the case of Arsenic acid H3AsO4 Sketch a species distribution diagram a versus pH for this acid in water The first second and third acid dissociation constants for this case are Kal 5 8E 3 K 2 1 1E 7 K 3 3 2E 12 H3ASO4 H H ASO4 H AsO4 H HASO4 HASO4 H AsO4 a Label the species for any lines that you put on the plot

A sample of sulphuric acid is 49 by mass 100 ml of it on titration with 12 N NaOH required 50 ml of NaOH solution The density of sample of sulphuric acid is 1 1 2 g ml 2 0 8 g ml 3 0 6 g ml J

Peripheral chemoreceptors adjust minute volume a rapidly in response to falling pH of cerebrospinal fluid rapidly in response to changes in blood pH c slowly in response to minor changes in blood pO2 d slowly in response to minor changes in blood pCO2

In this topic the energy kept on increasi ng then why all of a sudden did it go to 347 kJ Mean Bond Enthalpy In methane all the four C H bonds are identical in bond length and energy However the energies required to break the individual C H bonds in each successive step differ CH4 g CH3 g Hg Ac HH 427 kJ mol CH3 g CH2 g Hg AC HH 439 kJ mol 1 CH2 g CH g CH g Hg AC HH 452 kJ mol CH g C g H g Ac HH 347 kJ mol Over all reaction CH4 s C g 4H g

In a diffusion controlled reaction A B P at 43 53 C the viscosity coefficient of the solvent is 5 75 cP Diffusion coefficients of A B and P are 5 28 3 86 and 9 23 cm s respectively please calculate the rate constant of this reaction in dm mol s

For the reaction A B s 2Cg Kp 16 atm at 1000 K In a vessel of 20 5 litr moles of B are taken at 1000 K and then 2 moles of C are added Assuming volume occup by the solid to be negligible predict 1 Nothing can be predicted in the absence of sufficient data 2 Nothing would happen 3 An equilibrium will be set up with the formation of 0 5 moles of A 4 B and C would react completely to form A

3 An argon atom with average translation energy 3kT 2 k is Boltzmann constant is confined in a cubic box of volume V 0 6 m at 298K a What is the energy difference AE between levels n and n 1 b Calculate the ratio of AE and KT and comment if particle is in classical or quantum limit Marks 6 00

Consider the following manometer What is the gas pressure if the air pressure is equal to 760 mml 20 cm O 100 mmHg 860 mmHg 960 mmHg 660 mmHg Atmospheric pressure F 10 cm Mercury

62 2 0 mole of PC15 were introduced in a vessel of 5 0 L capacity of a particular temperature At equilibrium PC1 was found to be 35 dissociated into PC13 and Cl The value of K for the reaction a 1 89 PC13 g Cl g PC15 g c 1 33 b 0 377 d 13 3

Calculate the pH of a buffer solution that is 0 245 molal in CH3COOH Ka 1 75x10 5 and 0 375 molal in CH3COONa using the Davies equation to calculate y at 298 15 K calculated What pH value would you have if you had assumed that y 1

An equi concave lens made up of material of refractive index 1 5 has focal length of magnitude 10 cm The radius of curvature of any surface of the lens will be equal to 5 cm 10 cm 20 cm

A mixture of xenon and hydrogen gas is compressed from a volume of 100 0 L to a volume of 84 0 L while the pressure is held constant at 93 0 atm Caid the work done on the gas mixture Be sure your answer has the correct sign positive or negative and the correct number of significant digits

Please use the values in the resources listed below instead of the textbook values The rate of the electron exchange reaction between naphthalene C10H8 and its anion radical C10H8 in an organic solvent is diffusion controlled C10H8 C10H8 C10H8 C10H8 The reaction is bimolecular and second order The rate constants are as follows T K 305 295 291 275 k 109 M 1 s 1 2 64 2 21 2 05 1 49 Calculate the values of Ea AH AS and AG at 295 K for the reaction Hint Rearrange the equation below and plot In k T versus 1 T k Teaso Re AH RT M m KBT h Ea Hot AS MAGO 1 kJ mol 1 kJ mol 1 J K 1 mol 1 kJ mol 1

A manufacturer reports a FAAS sensitivity for nickel of 0 059 mg L using the principal atomic absorption line and a stoichiometric air acetylene flame Assuming linearity and the same operating conditions this implies that the blank corrected absorbance for a solution containing 1 07 mg Ni L should be approximately a 0 020 absorbance units b 0 040 absorbance units c 0 060 absorbance units d 0 080 absorbance units

Cu 2e Cu E 0 34 V Ag e Ag E 0 80 V For what concentration of Ag ions will the emf of the cell be zero at 25 C concentration of Cu is 0 1 M log 3 919 0 593 A 8x10 M B 7 10 M C 6 10 M D 5x11