Equilibrium Questions and Answers

Equal volumes of three acid solutions of pH 3 4 and 5 are mixed in a vessel What will be the H ion concentration in the mixture 1 1 11 x 10 3 M 3 3 7 x 10 4 M AIPMT Prelims 2008 2 1 11 x 10 4 M 4 3 7 x 10 3 M

a 3 70 10 70 b 3 30 10 30 c 3 70 27 What is the pH of a solution in which 25 0 mL of 0 1 M NaOH is added to 25 mL of 0 08 M HCl and final solution is diluted to 500 mL a 3 11 C c 12 of d 13 10 M STOH is added to 19 0 mL of

2 50 ml of a water sample requires 9 2 ml of N 50 HCI up to phenolphthalein end point and total 13 1 ml of the acid for complete neutralization Find the types and amount of alkalinity in the water sample

lle between 6 and 7 d remain unchanged 25 4 0 g of NaOH and 4 9 g of H SO4 are dissolved in water and volume is made upto The pH of this solution is a 7 0 c 2 0 d 12 0 b 1 0

25 ml of a 0 1 M solution of a stable cation of transition metal z reacts exactly with 25 ml of 0 04 M acidified KMnO4 solution Which of the following is most likely to represent the change in oxidation state of z correctly B C Z Z2 Z2 Z3 Z3 24 22 24 J X

The reaction 2A g B g 3C g D g is begun with the concentrations of A and B both at an initial value of 1 00 M When equilibrium is reached the concentration of D is measured and found to be 0 25 M The value for the equilibrium constant for this reaction is given by the expression AIPMT Mains 2010 1 0 75 0 25 1 00 1 00 2 0 75 0 25 0 50 2 0 75 3 0 75 0 25 0 50 0 25 4 0 75 0 25 0 75 0 25

2 10 c 0 02 d 0 1 149 What mass of AgI will dissolve in 1 0 L of 1 0 M NH 3 Neglect change in conc of NH 3 Given Ksp Ag 1 5x 10 6 K Ag NH3 21 1 6 x 107 At mass Ag 108 1 127 b 0 0056 g c 0 035 g d 0 011 g a 4 9 x 10 5 g 150 Consider the following statement and select correct option

Sulfur and Fluorine react in a combination reaction to produce sulfur hexafluoride In a particular experiment the percent yield is 83 1 This means that in this experiment A 4 50 g sample of fluorine yields 828

9 Select correct statement 1 When we add small amount of NaOH in acidic buffer solution pOH of solution is increases 2 When we add small amount of NaOH in basic buffer solution pH of solution is decreases 3 When we add small amount of water in acidic buffer solution pH of solution is decreases 4 When 100 mL of 0 2 M CH COOH react with 100 mL of 0 1 M NaOH buffer solution is formed 49 y 1 after a fe 2 faci fuerit a face pH i 3 Leia au fac a fac pH 1 4 100 f 0 2 M CH COOH faal 100 f 0 1 M NaOH aut facra va da

product of silver chromate will be 0 01 MK CrO 4 car shtc on factual 2 10 8 3 molata ch ae chi facudi quale fendall grun A 8 x 10 24 B 16 10 24 C 1 6 10 18 18

Calculate the solubility of copper II iodate in 0 32 M copper II nitrate Ksp is 7 4x10 8 M You should know that the Ksp must refer to the copper iodate because all nitrate compounds are soluble and strong electrol

At 200 C nitrogen oxide reacts with oxygen to form nitrogen dioxide as follows 2NO 0 2NO2 Kc 3 106 In a mixture of the three species at equilibrium we can accurately predict that A The concentrations of both NO and O will be much larger than the concentration of NO B The concentrations of both NO and O will be much smaller than the concentration of NO The concentrations of either NO or O and possibly both will be much smaller than the concentration of NO C D The concentration of O will be exactly one half the concentration of NO

20 mL of 0 032 M AgNO3 are mixed with 15 0 mL of 0 041 M of NaBr at 25 C Ksp of AgBr 5 x 10 13 at 25 C Then O the precipitation of AgBr occurs as the solution will be supersaturated with AgBr AgBr will not be precipitated as the solution will be unsaturated the resulting solution will be just saturated with AgBr and no precipitation takes place no prediction can be done regarding the spontaneity of precipitation 0

5 The heat of neutralization of a strong base and a strong acid is 57 kJ mol The heat released when 0 5 mole of HNO3 solution is added to 0 20 moles of NaOH solution is a 11 4 kJ b 34 7 kJ c 23 5 kJ d 58 8 kJ 2002

The frequency v of certain line of the Lyman series of the atomic spectrum of hydrogen satisfies the following conditions i It is the sum of the frequencies of another Lyman line and a Balmer line ii It is the sum of the frequencies of a certain line a Lyman line and a Paschen line

58 For a reaction A g B g at equilibrium The partial 68 pressure of B is found to be one fourth of the partial pres sure of A The value of AGO of the reaction A B is 1 RT en 4 3 RT log 4 2 RT en 4 4 RT log 4 4 3C H 9 C H C A g B Rich D A Rich and ens Juri Giala AB 1 RT en 4 3 RT log 4 g AGA 2 RT en 4 4 RT log 4 Torrent Q R T kilo

AIIMS The charge balance equation of species in 0 100 M acetic acid solution is given by a H OH c H OH CH COO d 2 H QH ICH COO b H CH COO

Which of the following is a buffer solution Question Type Single Correct Type 1 2 3 500 ml of 0 1 N CH3COOH 500 mL of 0 1 N NaOH 500 ml of 0 1 N CH3COOH 500 mL of 0 1 N HCI 500 ml of 0 1 N CH3COOH 500 mL of 0 2 N NaOH 500 ml of 0 2 N CH3COOH 500

4 Low pressure and low temperature 56 In the equilibrium reaction AgCl s 2NH aq Ag NH3 aq Cl aq Onnu Salt Increase in the concentration of Cl aq causes 1 AgCl s to decompose Agci s to precipitate 3 Ag NH aq to form 4 The NH aq concentration to decrease 4 56 3 fay AgCl s 2NH aq Ag NH aq C CH aq 1 AgCl s fra 2 AC s 3 Ag NH aq fact 4 NH aq 21 B

Which one of the following conditions will favour maximum formation of the product in the reaction A2 g B2 g X g AH X kJ 1 Low temperature and high pressure 2 Low temperature and low pressure 3 High temperature and high pressure onl De fon 4 High temperature and low pressure

2 Potassium dichromate is used to titrate a sample containing an unknown percentage of iron The sample is dissolved in H PO H SO mixture to reduce all of the iron to Fe ions The solution is then titrated with 0 01625 M K Cr O producing Fe and Cr ions in acidic solution The titration requires 32 26 mL of K Cr O for the 1 2765 g of the sample a Balance the net ionic equation using the half reaction method b Determine the percent iron in the sample

Given the reaction between 2 gases represented by A2 and B to give the compound AB g A2 g B2 g 2AB g At equilibrium the concentration of A 3 0 x 10 M of B 4 2 x 10 M 2 of AB 2 8 10 M If the reaction takes place in a sealed vessel at 527 C then the value of Kc will be 2 4 5 4 1 9 1 0 62 3 2 0

127 Silver ions are added to a solution with Br Cl CO AsO 0 1M Which compound will precipitate with lowest Ag a AgBr K 5 10 13 sp c Ag 2CO3 Ksp 8 1 10 2 b AgCl Ksp 1 8 10 0 d Ag 3 AsO 4 Ksp 1x 10 22

Solve the following problems Show your solution 1 What is the pH of 0 0235 M HCL solution 2 What is the pOH of 0 0235 M HCL solution 3 A solution with a H concentration of 1 00 x 10 7M is said to be neutral Why

a 8 10 b 6 4 x 10 c 8 10 130 The solubility of Ba 3 AsO 4 2 formula mass 690 is 6 9 x 10 2 g 100 mL What is the Ksp a 1 08 x 10 11 b 1 08 10 13 X c 1 0 x 10 15 d 6 0 10 13 131 The solubility of AgBrO formula mass 236 is 0 0072 g in 1000 mL What is the K

is incorrect 1 d20 d30 dso d vapour density of Equilibrium mix at certain decomposition 2 43 4 D Initial vapour density 1 2 d Vapour density of Equilibrium mixture 2 1 a 2 x Anital t D

a b 1 08 10 13 c 1 0 x 10 d 6 0 x 10 131 The solubility of AgBrO 3 formula mass 236 is 0 0072 g in 1000 mL What is the K a 2 2 10 8 b 3 0 10 10 c 3 0 10 X d 9 3 10 10 132 The solubility of PbF formula mass 245 is 0 46 g L What is the solubility product R a 1 08 x 10 11

Find freezing point temperature in Kelvin of liquid if vapour pressure of solid liquid are given by following expression Inp 10 Where P vapour pressure of solid 3000 K T 2000 K T In p 5 3 P vapour pressure of liquid Note All terms are in SI unit Fill your answer as sum of digits excluding decimal places till you get the single digit answer

A coffee cup calorimeter initially contains 125 g of water at a temperature of 24 2 C 8 g of ammonium nitrate NH4NO3 also at 24 2 C is added to the water and the final temperature is 18 2 C What is the heat of solution of ammonium nitrate in kJ mol The specific heat capacity of the solution is 4 2 J C g a 33 51 kJ mol b 39 5 kJ mol c 32 2 kJ mol d 37 3 kJ mol

123 Ksp of Zr3 PO4 4 in terms of solubility S is a 108 S7 b 4S d None of these 124 The solubility of electrolytes MX MX and MX is 1x 10 3 moles per litre Hence c 6912 S7

132 The solubility of PbF formula mass 245 is 0 46 g L What is the solubility product a 1 1x10 10 b 2 6 x 10 8 c 1 1 x 10 d 6 8 10 9 133 How many grams of MoC O formula mass 112 will dissolve in 15 of

27 A sample of CaCO3 s is introduced in to a sealed container of volume 0 654 litre and heated to 1000K until equilibrium reached The equilibrium constant for the reaction CaCO3 s CaO s CO g is 3 9x109 atm At this temperature calculate the mass of CaO s present at equilibrium in mg

125 A saturated solution of Ca3 PO4 2 has Ca 2 1 2 x 10 8 M and PO 1 1 6 x 10 5 M Ksp of Ca 3 PO4 2 is a 3 2 x 10 13 d None of these b 3 2 x 10 34 126 Which of the following is most soluble in water 33 c 2 048 x 101

2A g B g 3C g D g is start with the concentrations of A and B both at an initial value of 1 00 M When equilibrium is reached the concentration of D is measured and found to be 0 25 M The value for the equilibrium constant for this reaction is given by the expression 1 0 75 0 25 0 50 0 75 2 0 75 0 25 0 50 0 25 3 0 75 0 25 0 75 0 25 4 0 75 0 25 1 00 2 1 00 C

A mixture of 0 3 mole of H and 0 3 mole of 12 is allowed to react in a 10 litre evacuated flask at 500 C The reaction is H 2HI the K is found to be 64 The amount of unreacted 12 at equilibrium A B C D 0 15 mole 0 06 mole 0 03 mole 0 2 mole

115 Choose the correct set of True False for following statements 1 Silver chloride is more soluble in very concentrated sodium chloride solution than in pure water ii The pH of a buffer solution does not change on addition of small amount of an acid or a base iii Addition of NH4Cl does not affect the pH of a solution of NH4OH iv Degree of hydrolysis of ammonium acetate does not depend upon the concentration of ammonium acetate solution v A mixture of acetic acid and sodium acetate can act as buffer solution b FTTTF a TTFTT c TFTFT d FFTTT A 1 1

138 What is the molar solubility of Fe OH K 8 0 x 10 6 at pH 13 0 La sp a 8 0 10 18 b 8 0 x 10 15 c 8 0 x 10 17 139 What is the minimum pH necessary to cause a precipitate of Pb OH 8 0 10 K

117 150 mL of 0 0008 M ammonium sulphate is mixed with 50 mL of 0 04 M calcium nitrate The ionic product of CaSO 4 will be Ksp 2 4 x 10 5 for CaSO 4 a K sp b Ksp 118 In a saturated solution of AgCl NaCl is added gradually The c K sp d None of these ration of Agt is plotted

K for cyano acetic acid is 3 5 10 Then the degree of hydrolysis of 0 05 M sodium cyano acetate solution will have the following value 1 4 559 x 10 6 3 6 559 x 10 6 2 5 559 x 10 6 4 7 559 x 10 6

A container of volume V L contains an equilibrium mixture that consists of 2 mol each of gaseous PC15 PC13 and Cl at 3 atm and TK Some Cl is added until the volume is double keeping P and T constant Calculate moles of Cl added PC15 PCl3 Cl

122 What is the molarity of a saturated solution of CaCO3 Ksp 2 8 10 a 2 6 10 5 b 2 8 10 c 5 2 x 10 5 123 Kp of Zr3 PO4 4 in terms of solubility S is a 108 s sp d 5 6 x 10

What is the pH of the buffer formed by mixing 50 mL of 0 2 M NaH PO4 with 50 mL of 0 12 M HC Ka1 H3PO4 7 11x10 3 Kaz H3PO4 6 32x10 8 Ka3 H3PO4 4 5x10 13 a 4 05 O b 2 32 O c 7 02 O d 1 97

d None of these sp 118 In a saturated solution of AgCl NaCl is added gradually The concentration of Ag is plotted against the concentration of Cl The graph appears as a Ag cr b Ag CI c Ag cr d Ag cr

b 2 5 x 10 2 c 2 5 10 8 121 The solubility of a sparingly soluble salt A B in water is S moles per litre The solubility d 2 5 x 10 10 y c x yYsx y d sx y product has the value a s b x y S y 122 What is the molarity of a saturated colutio

the en CH 119 K of AgCl is 1x 10 10 Its solubility in 0 1M KNO will be a 10 5 moles litre b 105 moles litre c 105 moles litre d None of the 120 50 mL of a solution containing 10 3 mole of Ag is mixed with 50 mL of a 01 M HCL C

c 6912 S d None of these 124 The solubility of electrolytes MX MX2 and MX3 is 1x 10 3 moles per litre Hence the respective solubility products are a 10 4 x 10 27 10 12 c 10 8 10 8 32 10 2 x b 10 4x10 32 10 2 d None of these

For the reaction H COCO H O if the initial concentration of H CO and x moles litre of hydrogen is consumed at equilibrium the correct expression of K is 3 1 x 2 x 1 x 1 x 1 x

a TTFTT b FTTTF c TFTFT d FFTTT 116 A 1 litre solution containing NH4Cl and NH4OH has hydroxide ion concentration of 10 6 mol litre Which of the following hydroxides could be precipitated when the solution is added to 1 litre solution of 0 1 M metal ions I Ba OH 2 Ksp 5 10 III Mn OH 2 Ksp 2 10 3 a I II IV b IV II Ni OH Ksp 1 6 10 6 2 IV Fe OH 2 Ksp 8 x 10 16 c II and IV d II III IV

The equilibrium SO g NO g all four gases is taken in a one litre container the equilibrium concentration of SO3 would be A B C D 0 4M 0 6M 1 4M constant Kc for the reaction SO g NO g is 16 If one mole of 1 6M

not change but a changes 5 For an equilibrium H O s H O 0 which of the following statement is true 1 The pressure changes do not affect the equilibrium 2 More of ice melts if pressure on the system is increased 3 More of liquid freezes if pressure on the system is increased 4 None