General Questions and Answers

For the nuclear reaction A 8 Ax Ax 4 Y t 2 1600 yrs Z If initial activity was 107 dps how many a particles will be emitted per second after 4800 years Question Type Single Correct Type 1 25 x 106 s 1 2 2 5x 106 s 1 3 1 25 x 107 s 1

gas deco COCI g oses us CO g Cl g Blad V If one mole of He gas is added in the vessel at equilibrium at constant pressures then 000 a COCI increases b Moles of CO will increases c The reaction goes in forward direction d K 1 milom atni boyuboral nos munditions What would be the effect of increasing the volume of each of the following systems at equilibrium llw D d a 2CO g O g 2CO g 1919 b Ni s 4CO g c N O g Ni CO g erol onto 2NO g Bit mon by il 14 b Ka

The production of ammonia gas NH3 can be achieved from the reaction of nitrogen gas N2 with hydrogen gas H2 N2 3H2 2NH3 The isothermal and isobaric irreversible reaction consisting of 75 mol H2 with its partial pressure of 9000 kPa and the balance air is carried out in a 30 0 dm3 batch reactor at 475 0 K initially From a prior study it is determined that the reaction is first order with respect to N2 and second order with respect to H2 Air consisted of 79 mol N2 and the balance 02 N2 must be used as the basis of calculations Given the reaction rate constant as 10 0 dm6 mol2 min at 500 0 K and 2 5 dm6 mol2 min at 300 0 K 1 Construct a stoichiometric table for the above reaction All values should be in function of conversion X only by evaluating numerically all other

Starting from 2 propanol what are the appropriate sequence of steps that will lead to methyl propyl ether OH methyl propyl ether 1 NaOH 2 HBr 3 H SO4 heat 4 NaNH then CH3Br 1 NaOH 2 HBr ROOR 3 H SO4 heat 4 NaNH2 then CH3Br 1 H SO4 heat 2 HBr ROOR 3 NaOH 4 NaNH2 then CH3Br 1 H SO4 heat 2 HBr 3 NaOH 4 NaNH then CH3Br 1 NaOH 2 Hg OAc 2 CH3OH 3 NaBH4

vii L Ribose viii Lactose Tollen s reagent If X Y Z is number of mole of HIO consumed by 1 mole of sucrose 1 mo Y Z 1 of glucose 1 mole of fructose respectively Then value of is X HNO

1g of graphite is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atmospheric pressure according to the equation C graphite O g CO g During the reaction temperature rises from 298 K to 299 K If the heat capacity of the bomb calorimeter is 20 7kJ K what is the enthalpy change for the above reaction at 298 K and 1 atm

Illustration 6 72 A constant pressure calorimeter consists of an insulated beaker of mass 92 g made up of glass with heat capacity 0 75 J K g The beaker contains 100 mL of 1 M HCl at 22 6 C to which 100 mL of 1 M NaOH at 23 4 C is added The final temperature after the reaction is complete is 29 3 C What is AH per mole for this neutralization reaction Assume that the heat capacities of all solutions are equal that of same volumes of water

100 mL of 0 01 M KMnO oxidised 100 mL H O in acidic medium Volume of the same KMnO4 required in alkaline medium to oxidise 100 mL of the same H O will be MnO changes to Mn in acidic medium and to MnO in alkaline medium 2 2 02 HI 22 nM PE

9 In the following given numbers how many are the magic numbers 5 1 16 2 8 20 50 113 126 141 148 300 314 1 4 2 7 3 5 E 4 9 1 950 711

You need a 55 alcohol solution On hand you have a 660 mL of a 65 alcohol mixture How much pure water will you need to add to obtain the desired solution You will need to obtain mL of pure water mL of the desired 55 solution

If radius ratio r r is equal to 0 7 then coordination number of cation will be 1 2 4 6 8 Both 6 as well as 8 3

Example 7 42 Following two equilibria are established on mixing two gases A and C 02u i 3A g A g ii A g C g A C g K 1 6 atm P 0800 urfT P If A and C are mixed in 2 1 molar ratio calculate the equilibrium partial pressures of A C A C and K for the reaction ii Given that the total pressure to be 1 4 atm and partial pressure of A to be 0 atm at equilibrium

Illustration 7 153 K for the reaction N 0 2NO in chloroform at 291 K is 1 14 Calculate the free energy change of the reaction when the concentration of the two gases are 0 5 mol dm3 each at the same temperature GISIA R 0 082 L atm Kmot

Metal can be prevented from rusting by 1 3 Connecting iron to more electropositive metal a case of cathodic protection Connecting iron to more electro positive metal a case of anodic protection Connecting iron to less electropositive metal a case of anodic protection Connecting iron to less electropositive metal a case of cathodic protection Correct Answer 1 Status unattempted

5 Negative deviations from Raoult s law are exhibited by binary mixtures 1 in which the molecules tend to attract each other and hence their escape into the vapour phase is retarded 2 in which the molecules tend to repel each other and hence their escape into the vapour phase is retarded 3 in which the molecules tend to attract each other and hence their escape into the vapour phase is speeded up 4 in which the molecules tend to repel each other and han onog

An aqueous solution containing 28 by weight of a liquid A molecular mass 140 has a vapour pressure of 0 200 bar at 37 C Calculate the vapour pressure of pure liquid vapour pressure of water at 37 C 0 100 bar

The best indicator with their pH range given for the detection of end point in titration of a weak acid and a strong base is a Methyl orange 3 to 4 b Methyl red 5 to 6 c Bromothymol blue 6 to 7 5 d Phenolphthalein 8 to 9 6

Choose the right one Cu S CuS Copper sulphide does not dissolve under the action of either reagent 2M hydrochloric acid o reagent nitric acid because copper ion sulfide ion oxonium ion H concentration is not high enough to that the copper ion sulfide ion concentraion sufficiently decrease increase

When rain is accompanied by a thunderstorm the collected rain water will have a pH value a slightly lower than that of rain water without thunderstorm b slightly higher than that when the thunderstorm is not there

Be sure to answer all parts Complete the following precipitation reaction with balanced molecular total io equations Remember to include the proper physical states and charges of ions charge number is not I place the charge number before the charge sign If a not include the charge number in the formula Na S aq ZnSO4 aq Molecular Total ionic Reactants Products Donn

Enter your answer in the provided box One of the first steps in the enrichment of uranium for use in nuclear power plan displacement reaction between UO and aqueous HF UO s HF aq UF4 s H O 0 unbalanced How many liters of 4 33 M HF will react with 6 16 kg of UO

50 ml of 0 5 M oxalic acid is needed to neutralize 25 ml of sodium hydroxide solution the amount of NaOH in 50 ml of the given sodium hydroxide solution is 4 20 g 1 10 g 2 80 g 3 4 g

The reaction CO g C s 2CO g has K 5 78 at 1200 K The reaction CO g C s 2CO g has K 5 78 at 1200 K Calculate the total pressure at equilibrium when 4 52 g of CO is introduced into a 10 0 L container and heated to 1200 K in the presence of 2 31 g of graphite Express your answer to three significant figures and include the appropriate units Ptotal 1 70 atm Submit V Correct Part B Previous Answers Ptotal Repeat the calculation of part A in the presence of 0 44 g of graphite Express your answer three significant figures and include the appropriate units A 19 Value atm Review Constants Periodic Table

Which of the following is an example of liquid dishwashing detergent Question Type Single Correct Type Me 1 1 Me CH 15 N Me Br I Me 2 Me OX SO3Nat 3 C9H19 OO CH CH20 5 CH CH OH

9 Magic number elements are those isotopes of elements 1 In which the number of protons or neutrons is 2 8 20 28 50 82 or 125 2 Which are relatively more abundant 3 Which are unusually stable bus 4 All of these

2x Heat of formation at standard state for CO g H O l and Hydrocarbon C H x are 400 kJ mol 300 kJ mol and 50 kJ mol respectively If heat of combustion of C H2x at standard state is 1450 kJ mol the correct formula of Hydrocarbon is x 2 C3H6 1 C H4 3

31 Which statement s is are correct Ja All Bronsted bases are also Lewis bases All Bronsted acids are not Lewis acids Most cations are acids and most anions a bases d All Bronsted bases are also Arrhenius bases

1 Volume of one equivalent O2 is 5 6 litre at STP 3 2 When 10 ml H SO4 is added to 10 ml water then total volume becomes 20 ml 3 Generally combustion exothermic reaction reaction is an dic 4 Atomic radius of gallium is less than that of

What mass of aluminum is required to react in order to produce 12 8 g of aluminum oxide according to the following reaction molecular weights MnO 86 94 g mol Al O3 101 96 g mol 4 Al 3 MnO2 3 Mn 2 Al O3

Which of the following statement is 1 point not true for Lindeman approach O O O The bimolecular step does not account for activation energy dependent unimolecular reaction are usually accompanied by a preceding bimolecular step The internal degree of freedom of molecular are not ignored The internal degree of freedom of molecular are ignored

How many total moles of ions are released when the following sample dissolves cor Enter your answer in scientific notation 8 66x 10 6 formula units of Sr HCO3 2 x 10 mol

4 After 20 min the amount of certain radioactive substance disintegrate was 15 16th of the original amount What is the half life of the radioactive substance 1 4 2 6 3 5 4 8

wow of w moales of ethylene no M Law of consination of 1 mole 100 no of 28 moles mass s of 100 28 mass moles of polythere polythene NA molecules 100 NA molecules moles 100 28 100 28 NA X 38 100 100 28 mol niche wala kese hua no of moles of polythene nikal ke uske molar mass se multiply hoga to iven mass avega and vhi qus me puch rha

15 Photoelectric emission is observed from a surface when lights of frequency n and no incident If the ratio of maximum kinetic energy in two cases is K 1 then Assume n n threshold frequency is 1 K 1 Kn n X 2 3 Kn n 1 K K 1 Kn n

c Simple cubic d None of these 8 Polonium crystallizes in a simple cubic structure The edge of the unit cell is 0 236 nm What the radius of the polonium atom a 0 144 nm b 0 156 nm c 0 118 nm d 0 102 nm

1 The periodic table consists of 18 groups An isotope of copper on bombardment with protons undergoes a nuclear reaction yielding element X as shown below To which group element X belongs in the periodic table 29 Cu63 H 6n He a 2 H XA 01

AH olubility of a solute in a solvent say H O is dependent on temperature as given by S Ae where AH is heat of reaction olute H O solution AH tx For a given solution variation of log S with temperature is shown graphically Hence solute ogs A CuSO4 5H O B NaCl C Sucrose 1 T D CaO Correct Answer

c 8 14 9 d 8 4 2 20 What would be the effective number of atoms per unit cell in end centered cubic unit cel this type of unit cell exist in nature b 2 a 1 d 4 c 3 21 In the body centered cubic unit cell and simple cubic unit coll

0 A mixture of 3 mol CH3OH and 4 mol C2H5OH is mixed to prepare an ideal solution The tota vapour pressure of solution is Vapour pressure of CH3OH 20 mmHg and Vapour pressure of C2H5OH 30 mmHg 1 17 14 mmHg 3 30 mmHq 2 25 71 mmHg 4 50 mmHg

1 mol of monoatomic ideal gas perform the following operation P C A B V Select the correct statement or relation 1 A to B is endothermic process 2 B to C is exothermic process 3 C to A is exothermic process 4 Work done in cyclic process ABCA is zero

30 Which set of quantum numbers is not consistent with theory 1 n 2 1 1 m 0 s 1 2 1 2 n 4 1 3 m 2 s 2 3 n 3 1 2 m 3 s 1 2 1 3 m 3 s

A metal oxide has the formula Z O3 reduced by hydrogen to give free metal and water 0 1596 g of the metal oxide requires 6 mg of hydrogen for complete reduction The atomic weight of the metal is

SolveLancer Test For FeSO4 6H O which statement is correct related to moles SolveLancer Test a 10 Mole of Fe Mole of O b 5 x Mole of Fe Mole of O c 9 x Mole of Fe Mole of 0 2 d Mole of Fe 5 x Mole of O

The ratio of masses of an element A attached with the fixed mass of another element B in their two compounds is 2 3 If 48 mass of A is attached with 24 mass of B in first compound then what mass of A is attached with the 12 mass of B in the second compound 1 72 2 36 3 24

31 0 24 g of a volatile gas upon vaporisation gives 45 mL vapour at NTP What will be the vapour density of the substance Density of H 0 089 a 95 93 c 95 39 1996 b 59 93 d 5 993

andard electrode potential data are useful for understanding the suitability of an oxidant in a redox reaction Some half cell reactions and their standard potential are give elow InO aq 8H aq 5e Mn aq 4H 0 1 E 1 5 V 0 aq 14H aq 6e 2Cr aq 7H O 1 E 1 38 V 3 aq eFe2 aq E 0 77 V 12 g 2e2Cl aq E 1 40 V entify the correct statement s regarding the quantitative estimation of aqueous ferrous nitrate in solution 1 MnO can be used in aqueous H SO4 2 Cr 0 can be used in aqueous H SO4 MnO can be used in aqueous HCI 3 Cr O can be used in aqueous HCI

23 With increasing principal quantum number the energy difference between adjacent energy levels in atoms 1 Decreases 2 Increases 3 Remains constant 4 Decreases for low 7 and increases for high 7

In quantitative analysis of second group in laboratory H S gas is passed in acidic medium for precipitation When Cu and Cd react with 2 KCN then for product true statement is a K Cu CN 4 more soluble less stable b K Cd CN 4 c K3 Cu CN less stable d K Cd CN 3 more stable 2000

33 The electron identified by quantum numbers n and I i n 4 1 ii n 4 1 0 iii n 3 1 0 iv n 3 1 1 Can be placed in order of increasing energy 1 iii iv i ii 2 iii iv ii i 3 i iii ii iv 4 iii i iv ii

0 635 x 10 kg of a substance of molar mass dissolved in 3 190 10 kg mol 1 was 30 5 x 10 kg of a solvent If the depression in the freezing point is 0 62 C find the molal depression constant of the solvent 2 marks