Physical Chemistry Questions

D 3 1 the synthesis ciation of HI D 0 02 s 81 When NaNO is heated in a closed vessel O is liberated and NaNO is left behind At equilibrium A addition of NaNO favours reverse reaction B addition of NaNO favours forward reaction C increasing temperature favours forward reaction D increasing pressure favours forward reaction

10 M pyridine solution to which 0 3 mol of pyridinium chloride CH NH CI has been added assuming no change in volume Calculate the pH of a solution which results from the mixing of 50 0 ml of 0 3 M HCl with 50 0 ml of 9 4 MINH K NH 1 8 10 5 33 Calculate the pH of a solution made by mixing 50 0 ml of 0 2M NH CI 75 0 ml of 0 1 M NaOH 0 32

If a solid AB having ZnS structure is heated so that the ions along two of the axis passing through the face center particles are lost and bivalent ion Z enters here to maintain the electrical neutrality so that the new formula unit becomes Ax ByZc Report the value of x y c

of 200 mL of 1 M KOH is added to 200 mL of 1 M HCl and the mixture is well shaken This rise in temperature T is noted The experiment is repeated by using 100 mL of each solution and increase in temperature T is again noted Which of the following is correct diw sao s a T T ogmat cab driw 292651n d 2 b T is twice as large as T d belostieny amma 0 2 1 POOL 2 c T is twice as large as T betoibsn od tonnes b d T is four times as large as T of formation of Car On

1 4 2 3 The gas phase reaction 2NO g N O4 g is an exothermic reaction The decomposition of N O4 in equilibrium mixture of NO g and N O4 g can be increased by JEE Main Online 2018 1 Addition of an inert gas at constant volume 2 Increasing the pressure Lowering the temperature 4 Addition of an inert gas at constant pressure

nT The figure below shows the plot of gas at two different temperatures BHU 2006 AIIMS 2007 J mol K PV nT EEE P Read the following statements concerning the above curves i The dotted line corresponds to the ideal gas behaviour ii T T versus P for oxygen T2 T iii The value of PV nT on the y axis is the same for all gases a i only c All of these Which of the above statement is true at the point where the curves me b i and ii only d None of these

Assigned Mass of Temperature evaporating C dish cover 10 20 30 40 50 60 70 80 37 81 g 37 65 g 36 95 g 37 80 g 36 50 g 37 75 g 35 98 g 37 81 g Mass of evaporating dish cover KCI solution 48 75 g 50 42 g 47 82 g 48 19 g 47 49 g 50 08 g 48 29 g 48 64 g Mass of evaporating dish cover dry KCI 40 54 g 40 99 g 39 81 g 40 63 g 39 75 g 41 52 g 39 86 g 41 37 g 5 Mass of KCI 4 2 6 Mass of water 3 4 7 Mass of KCI per 100 g of water

3 Which one of the following is not a reversible reaction a 2HI g H g 12 g b PC15 g PC13 g Cl 2 g c 2KC103 s 2KCl s 302 g d CaCO3 s CaO s CO2 g Tog

C sp 2 C2 sp sp sp C3 sp 3 sp a H H C C H C3 Acrylonitrile C Z

Forward and reverse rate constant for the reaction CO g N g CO g N O g exhibit the following temperature dependence Temperature K 1200 1500 16 k M s 9 1 x 10 11 2 7 x 10 9 k M s 1 5 105 2 6 105 Is the reaction endothermic or exothermic Explain in terms of kinetics If your answer is exothermic fill your answer as 1 for endothermic fill your answer 2 in OMR

4 Calculate the strength in percentage W V moles per litre or molarity number of gram equivalents of the solute and normality of the following solutions i 9 125 g of HCl in 200 mL of its aqueous solution ii 60 g of NaOH in 3 L of its aqueous solution iii 14 7 g H SO4 in 500 mL of its aqueous solution iv 296 g Ca OH 2 in 10 L of its aqueous solution

A 100 Fl 50 153 151 Mass amu to determine the atomic mass of europium The peak representing Eu 151 has an exact mass of 150 91986 amu and percent intensity is assumed be to exactly 91 610 the peak representing Eu 153 has an exact mass of 152 92138 amu and percent inten 100 00 Express your answer to two decimal places with the appropriate units View Available Hint s 11 Intensity

A small amount of sodium chloride NaCl is dissolved in a large amount of water Imagine separating this process into the four stages sketched below These sketches show only a portion of the substances so you can see the density and distribution of atoms and molecules in them A D NaCl H O Use these sketches to answer the questions in the table below B The enthalpy of solution AH is positive when soln NaCl dissolves in water Use this information to list the stages in order of increasing enthalpy Would heat be absorbed or released if the system moved from Stage A to B What force would oppose or favor the system moving from Stage A to B Check all that apply 0 00 absorbed released neither absorbed nor released none ionic bonding force covalent bonding force metal bonding force hydrogen bonding force dipole force C ion dipole force dispersion force DO X solution 5 13

If the solubility of cholesterol in methanol were 1 g 96 mL at 20 C and 1 g 4 2 mL at 80 C what is the absolute minimum amount of methanol needed to recrystallize 5 01 g cholesterol Report the number of mL to the nearest whole number OGMU 2020

In the reaction A 3B2C initially 10 moles each of A and B were taken If equilibrium pressure is 8 atm and of A 20 then K P will be 1 1 2 118 3 1 16 4 13X 2

Specific Gravity Measure the specific gravity in the image below and input your answer Answer must include 3 significant figures 1 070 1 060 1 050 1 040 1 030 1 020 1 010 1 000 20 C 100 80 60 40 20 0 0

C4 C5 C6 C7 4 sp sp 3 8p H H CA Cs d H 4 f Methyl methacrylate H C H H

Number of equivalent of HCI present in 100 mL of its solution whose pH is 4 H HZ nouday 1 10 4 2 10 3 3 10 2 4 10 5

Suppose 4 61 g of zinc was allowed to react with hydrochloric acid to produce zinc chloride and hydrogen gas How much zinc chloride in grams should you get 1 Zn s 2 HCl aq 1 ZnCl2 aq 1 H2 g

a Many important compounds in the chemical industry are derivatives of ethylene C2H4 One is acrylonitrile What are the indicated bond angles in acrylonitrile angle a angle b angle c a H H 120 Acrylonitrile 1200 900 109 5 1800 1200 N

m constant equilibrium is established K 6 8 x 10 2 and 1 0 mol of sulphur are heated to 90 C in a 1 0 litre ves what will be the partial pressure of H S at equilibrium The equilibri At 90 C the following H g S s H S g If 0 2 mol of hydrogen

The standard reduction potentials for the following reactions are given below Pyruvate 2H 2e lactate E 0 190 V NAD 2H 2e NADH H E 0 320V What is AG for the overall spontaneous reaction make use of the relationship between AE and AG O Ok J mol O 25 kJ mol O 15 kJ mol O 25 kJ mol

Sigma bonds can form between different types of orbitals The main criterion for sigma bond formation is that the two bonded atoms have valence orbitals with lobes that point directly at each other along the line between the two n The images below show the shapes of two orbitals on adjacent atoms Choose all of the combinations that will lead to formation of a sigma bond Select all that apply O O d 2 2 day W

o bonds bonds a H H C H C2 S Acrylonitrile

2 A student needs to determine the density of two metal objects The first object is a cube and the second object is a rectangular bar The student uses calipers to measure the length of the objects a What is the density in grams per milliliter of the metal cube if it has a mass of 84 55 g and an edge length of 2 16 cm b mL What is the density in grams per milliliter of the rectangular bar if it has a mass of 186 7 g and measures 4 26 cm in length 1 42 cm in width and 13 21 cm in height mL

136 E for the cell Zn Zn2 aq Cu 2 aq Cu is 1 10V at 25 C the equilibrium constant for the reaction Zn Cu2 aq Cu Zn2 aq is of the order of a 10 28 c 10 18 b 10 3 d 10 17 Karnataka CET Med 2012

9 What type s of intermolecular forces exist between NH3 and PO43 A dispersion forces B dispersion forces ion dipole and dipole dipole C dispersion forces and dipole dipole D dispersion forces and ion dipole E dispersion forces ion dipole dipole dipole and hydrogen bonds OE dispersion forces ion dipole dipole dipole and hydrogen bonds OC dispersion forces and dipole dipole OD dispersion forces and ion dipole B dispersion forces ion dipole and dipole dipole OA dispersion forces

Use the mass spectrum of strontium to estimate the atomic mass of strontium A atomic mass Value Units A 50 84 86 Mass amu Estimate the mass and percent intensity values from the graph to three significant figures The peak representing Sr 84 has a percent intensity of 0 700 the peak representing Sr 86 has a percent intensity of 11 9 the peak representing Sr 87 has a percent intensity of 8 50 the peak representing S a percent intensity of 100 Express your answer to three significant figures and include the appropriate units Intensity 100 87 88

A solution is made by mixing 50 0 g of A molar mass 68 0 g mol and 50 0 g of B molar mass 35 0 g mol At 25 C the vapor pressures of pure A and B are 285 and 132 mmHg respectively Calculate the information requested below Enter your calculated answer below and be sure to upload your work and calculations receive full credit Note Correct answers without supporting work earn 0 points a Mole fraction of A in the solution b Vapor pressure of solution at 25 C in mmHg c Mole fraction of A in vapor above the solution

d Many important compounds in the chemical industry are derivatives of ethylene C2H4 One is methyl methacrylate What are the indicated bond angles in methy methacrylate angle d angle e angle f H Methyl methacrylate 90 109 50 120 1800

In homogeneous catalysis the rate of reaction depends upon the a concentration of catalyst surface area of catalyst LOTURO c physical state of the catalyst d all of these 8 beisgold or les are as he trebbe tenaque B B Gelos labiellus sbinglu SrasmA IT

The standard emf of the celloltot odi quoe roshura A car Ag s Cd CdC12 aq 0 1 M AgCl Agenci abvd in which the cell reaction is UM 2C1 is 0 6915 V aq Cd 2AgCl2Ag Cd aq at 0 C and 0 6573 V at 25 C The enthalpy change of the reaction at 25 C is a 48 179 kJ c 123 5 kJ b 234 7 kJ d 167 26 kJ

What would be the reading of the liquid in the following graduated cylinder reported to the proper number of significant figures 6

You are given the following substances with their melting and boiling points Substance Melting point C Boiling point C X 219 Y 119 Z Identify the physical states of X Y and Z at room ton 680 449 78

7 The first disinfectant used by Joseph Lister was called carbolic acid This substance now is known as phenol C6H5OH pKa 10 90 What is the pH of a 0 10 M solution of phenol d 5 95 e 5 45 a 3 50 b 8 55 C 6 50

In this reaction CO2 g CF4 9 2COF2 g what would be the effect if the volume of the system is decreased by increasing the pressure Equilibrium shifts toward the product No shift takes place Equilibrium shifts toward the reactant None are correct

9 Using the Model screen add bonding domains to the central and dashes from Model 2 draw each molecule s shape Bonding Domains Around Central Atom 2 3 4 Drawing of Shape 101 Electron Geometry Linear Bond Angles 180

Which of the choices below shows the correct method for converting 50 g into ounces 18 454 grams g 1 0 pound lb 16 ounces oz 1 0 pound lb Select one 50g 10 1 8oz 1 0lb 50g 454g 1602 1 8oz 50g 454g 1 0lb 10 1 80z 1 0lb 50g 101h 160z 1 8oz SODA 50 g

2 Having now performed two chromatogram experiments suggest two possible applications for paper chromatography other than the identification of metal ions Admittedly your experience is limited here but let your imagination go 3 During a chromatography experiment a student calculated two R values They are A 0 62 and B 0 30 The solvent front for the original chromatogram was 12 0 cm If A and B were run on a second chromatogram and the solvent front was 25 0 cm how far apart would A be from B

If atmospheric pressure suddenly changes from 1 00 atm to 0 899 atm at 298 K how much oxygen will be released from 4 80 L of water in an unsealed container please put answer in scientific notation amount mol

Following graph represents variation of half life period t1 2 of a nth order reaction with Ao initial concentration of the reactant 1 2

The rate of a first order reaction is 2 5 x 10 mol L min at 0 25 M concentration of reactant The half life in min of the reaction is O 69 3 O 43 5 O 76 6 38 7

Although fluorite is its chief mineral source fluorine can also be obtained as a by product of the production of phosphate fertilisers These fertilisers are derived from phosphate rock 3Ca3 PO4 2 CaF2 What is the maximum mass of fluorine that could be extracted as a by product from one ton of phosphate rock a 75 39 kg F2 b 37 68 kg F2 c 15 kilomoles F2 d 18 84 kg F2

sed on the equations for today s reaction 2 2 5 03 1 S406 21 Cu 41 2 Cul s 1 w many moles of copper would be used in a reaction that needed 5 mol of S 0

In the narrative Tom lures his friends into whitewashing the fence while he enjoys with the things he gets in exchange Which of the following phrases describes how more of his friends became victims O alacrity in his heart O with reluctance in his face the slaughter of more innocents

pands then the external pressure is less than the pressure of the system Thus Per Pin dp If compressed Per P of system thus Per cat cams stage pin dp General equation Pea Pintap can u explain why it is Pin dp minus in the first case and Pin dD plus in the second caro

Calculate the work done during combustion of 0 138 kg of ethanol C H5OH 1 at 300 K Given R 8 314JK mol molar mass of ethanol 46gmol A B 7482 J 7482 J Correct Answer

A catalyst is a substance which Itself undergoes a permanent chemical change O Alters the Gibb s energy of reaction Catalysis non spontaneous reactions Increases the rate of reaction

4 Consider the reaction 2x g 3y g 2zig constant temperature and volume partial pressure of x p varies as follows Time min 0 P mm Hg 800 400 200 200 Order of the reaction is 1 0 2 1 2 0 5 4 2 temperature having energy gre 7 38 1 2 7 3 25 57 If two first K gets doubled when the 17 C By what m C K 1

For the reaction HF aq H aq F aq K 7 2 x 104 Calculate the hydrogen ion concentration H for a 0 63 M solution of HF in water Don forget to set up the table first