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Question 1
In some regions in space around the nucleus y2 = 0. What is the name given to such a region?
These regions are known as notes of the orbital.

Question 2
Is there any difference between the energies of two orbital in an atom represented by the quantum numbers.
n = 3, l = 2, m = +1 n = 3, l = 2, m = -1 Energy Value is decided by the Values of n and l quantum numbers. Since they are some, two orbitals will have some energy levels.

Question 3
An intermetallic compound XY crystallises in a cubic lattice in which both X and Y have coordination number of eight To what crystal class does the unit cell belong?
It is Body centred cubic type of packing in which each X and Y will have coordination number eight.

Question 4
Define Mandard enthalpy of formation.
It is the enthalpy change of a reaction, in which one mole of a compound is formed from its constituent elements in their most stable state at l atm and 298K

Question 5
What is the use third law of thermodynamics.
It is used to calculate the entropies of a substance at different temperature.

Question 6
Arrange the following compounds in the increasing order of the their reactivity towards water (CH₃CO)₂O, CH₃CONH₂, CH₃COCL, CH₃CO.OCH₃
CH₃CONH < CH₃ COOCH₃ < (CH₃CO)SO < CH₃COCL

Question 7
How is cathodic protection of iron different from galvanization.
In cathodic protection iron is connected to more reachen metal of more reachne metal takes place than of iron. due to higher oxidation. In Galvanization iron is coated with Zinc which presents the rusting of iron by cutting of the supply of air and moisture.

Question 8
What type of compounds can under go iodoform test?
Compound containy following groups can lendergo iodoform list. H l CH3 - C - or CH3- C- l ll OH O where the fourth bond of carbin can be satisfied by H or R or A

Question 9
For a first order reactio what are the units of rate constant - K?
R = K[A] k = R = ~~mol~~ L-1 sec-1 A ~~mol~~ L-1 K =Sec -1 Where sec is later the unit os time [Note it can be any other unit of time]

Question 10
What is Vapour phase ritration ?
It is the heating of hydrocarbun in Vapour state willninitric and Vapours at a high temperature R-CH3 + HNO3 -------> RCH2NO2 + H2O alkane nitric acid nitroalkane water

Question 11
use the concept of hybeudisation to explain the shape of SF₆ molecule
of suphur SP³d² hybridisation takes place and results ink octahedrol geometry with respec to sulphur Molecule SF₆ is Octahedral in shape .

Question 12
Write a note on:- a) Clemmonsons's condensation b) Williamson's synthesis
a) Clemmenson's condensation:- It is a method of converting >c = 0 Ccorbinyl group) to - CH₂. by using Zn - Hg ammalgam and lonc. hee. CH3 CH3 Zn-Hg C = O + 4(H) ----------> CH2 + H2O / Conc. HCl / H H (CH3CH3) b) is a method to prepare ether by reacting on alkyl halide and a sodium salt of alcohol RCl + R1 ONa -------> ROR1 + Nacl

Question 13
How is a F - centre produced in a crystals of ionic alkali halide
When alhali metal halide crystals are heated in alhole metal vapours. F - centres are crealed. (i) Metal ionized as follows M ---> M+(g) + e- (ii) halide ions is cape from crstals lattice and combine with metion to make metal halide on surface leaving hehind anionic vawnies . The e^- trapped in the anion Vacancy of crystal lattice is called F- centre.

Question 14
How will you distinguish between eltonoic acid and methanoic acid
Take methonic acid and ethonic acid in two list tubes add few drops of acid fied K₂ CR₂ O₇. and heat gently. The test tuho which contains methanoic acid- brish efferivescenes can be scan, A coloulen odourten gas is given out which turm limewater milhy. HCOOH ------------> CO2 + H2O K2CR2O7 Ca(OH)2 + Co2 ----------> CaCo3 + H2O

Question 15
Which of the following solutions each of which is 1 x 10^-2m has the lowest freezing point. (i) CH₃OH solution (ii) NaCl soln (iii) CaCl₂ soln. (iv) sugar soln
DT_f ( depresium in freezing point depends on K_f m and no of particles present in soln. In all given examples malality is 8 ame 1 x 10^-2m. But CaCL₂ on dissovation forms 3 particles per unit formula where an NaCL₂ and CH₃OH and sugar mocuiles do not disocidled therefore the largest number o fparticles are present in CaCl₂ soln so DT_f is largest in CaCl₂ hence CaCl₂ soln. will have the lowest freezing point.

Question 16
Account for the following a) B. p of acid amider is higher than that of carbusytic acid b) phenols are acidic in nature
a)(4)o H ll / R-C-N H (4) o ll R-C-O-H 2 1 There are more silis ter Hydrogen bundy in acid onside than in carbuxylic and. therefore stronges hydrogen bonding in acid onsides. Acid oncide has highes b. p than acid (image) b) (i) Renonance structure of plenol tue charge on oxygen attrach the par'v of electron toward itself and releases hydrogen atom as it ion. (ii) The resultan 1- Phonoxide ion is also stabilized by resonance (image) (iii) Resonance structures of phonoxide ion suggest they ar more stable than phenol because these is only one charge whereas in phnol some energy is necded to seporate tue and -ne charges over moleuele (iv) Hence equilidrium shifts towards right hand side and H⁺ ions are released.

Question 17
Conc. H2SOY has a density of 1.95gmL^-1 and is 9 & 1. sulphuric acid by mass. Calculate the molarity of this solution.
Molarity of soln = no of moles per L of soln. 9 & 1. by mass means 98g of sulphuric and in 100g of soln. no of moles of 98/98 = 1.0 mol. Vol. of soln = Man of solution/Density ofsolution = 100g/1.95gmL^-1 = 51.28mL. 51 28 mL of soluiton contains 1 mole 1000 ml of soln contains 1/51.28 x 1000 = 19.5M

Question 18
How is Gibb's free energy related to enthalpy, entroly and temperature of a system? How is this lesed in determining the spontaneity of a process.
Change in free energy (DG) is related to chang in enthalpy (Dit), change in entropy LDs and temperature as follows: Dg =Dh - TD S. for a reaction to be spontaneous DG should be negative (i) It DH is -ne and DS is the, then both these factor will make DG -ve and DS is slrotne (ii) if DH is the thern DL is -ve only when TDS > DH athen is only possible al - high temperature (iii) If Dit and DS both are negative then reaction is only possibel when DH > TDS. and it is only possible al- low temperature

Question 19
Predict the products f eletrolysis of agueous acidifies solution of copper (II) chloride using platenum elubodes
There are two equilibria in soln. image (i) Therefore the products are copper at cathode and O₂ at anode. (ii) Constant increase is It+ ions,makes the soln acidic (iii) conuntratiun of Cu²⁺ ions decreases

Question 20
The rate of raction triples when temperature changes from 20 to 50 ⁰C. Calculate the cactivation energy for such a reaction (R = 8.314 JK^-1 mol^-1)
(image)

Question 21
Write a note on mechanism of nitration of benzine.
(i) Netrating mixture is able to release nitronium ion, NO₂⁺ HNO3 + H2SO4 -----> NO2+ + H2O + HSO4- Conc. Conc. (ii) Nelronium ion is attacked by electron rich cloaid f benzlne (image) Therefore onerall reaction is (image)

Question 22
Calculate the equilibrium constant at 25⁰C for the reaction corresponding to the cell (image) Calculate the maximum wish that would be obtainged by operation of this cell if (image)
(image)

Question 23
The half life of a first order reaction A ---B is minutes. How long will it take [A] to reach 25% of its initial concentration?
(image)

Question 24
a) Write IUPAC names of the following:- (i) CH₃ - CH = CH - CH - OH (ii) (image) b) Write the structural formaulae of the following (i) 4 - Chloroacetaphenone (ii) N, N -ethylpropaneamine
(image)

Question 25
Defferential between rate constent and rate of reaction.
Rate constant	Rate of reaction
(1) It is equal to rate of reaction when the concentration of reacting species is taken as unity	(1) It is the change in cocentration of the reactions or produces per unit time
(2) Unit depends on order of reaction	(2) Units are mol L-1 per unit time

Question 26
The resistance of 0.1M Ag No₃ Solution is 35 n. If the cell constant is 0.375 cm^-1 calcutlate the molar conductivity of solation
(image)

Question 27
Calculate the uncertainty in velocity of an electron. if the uncertainty in its position is 10^-10m. ( h = 6.6 x 10^-34 Kgm² sec-1 mass up electron = 9.1 x 10^-31b Kg)
(image) If the uncertainty in the velocity is of such a high magnitude, it is irrelevant to refer to the actual velocity of electron.

Question 28
What happens when:- a) Neutral Fecl_3b is added to a suspension of phenol in water b) A mixture of ethyl alcohol and ofacial acili in heated in the presence of conc. H₂SO₄ c) Few drops of Bromine water are added to aniline and shaken well.
a) A purple colouratiun is obtained (image) b) An ester with fruily small is Obtained (image) c) (image) A white ppt os 2, 4, 6 - tribromoaneline is obtained

Question 29
Solid iron has bcc structure, and its density is 7.86g/ml calculate (i) the edge length of the unit cell (ii) the radius of the Fe atom. [ molewlau mass of Fe = 55.8] (image)
(image)

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