IGNOU BCHCT-133 December 2023 Previous Year Question Paper

Q1.Write your Enrolment number, course हु है and volume for an adiabatic process using code and part title clearly on each of the the following expression : two answer books. yl Tj M

(iii) Marks are indicated against each व Vy question. c

(b) Calculate the enthalpy change for the

(b) Differentiate between the terms following reaction : ‘dissociation’ and ‘ionization’ with the help CHy

(g)+20,

( g) C0,

( g) +2H,0(I) of suitable examples. 3 है Given that the enthalpies of formation of 5.

(a) When will AG° be negative for an ilibri tion 2 CH,

(g), CO>

(g) and H,0 are 74.8, -393.5, equilibrium reaction ? 2 and — 286 kJ mol-! respectively. 3

(0) For the conversion of oxygen to ozone :

Q2.(g) = 20;(g

Q3.(a) What is residual entropy ? What kind of 2

(8)

(8) species show residual entropy ? 2 K, =6.25x10* at 300°C :

(b) 2 moles of neon gas is taken in a cylinder

(i) What is the value of Ke if the equation fitted with massless and frictionless piston is written as $0,

(g) = 03

(g) ? and occupies a volume of 2 dm’ at 298 K. हा हि T हु है

(ii) What is the value of K. for the ‘he gas undergoes isothermal reversible conversion of ozone to oxygen at this expansion to 10 dm’. If the gas behaves temperature ? 3 ideally, calculate the entropy change for 203

(g) = 30,

(g) the process.

Q4.(a) How would the degree of ionisation of a

Q5.(a) Write the equilibrium constant (Kp) weak acid change with the dilution of its expression for the following equilibrium solution ? Explain. 2 reactions : 2

(b) Calculate the degree of ionisation and concentration of H,0* ions in 0.1 M

Q6.CO

(g)+H,0

(g) = CO,

(g)+H,(g

(2) +H20

(e) = CO2

(e)+H2

(2) solution of acetic acid at 298 K.

Q7.No

(g)+3H2

(g) = 2NH3

(g) [Given : Ka (acetic acid) = 1.8107 at

Q8.1. 0. [6]

Q9.(a) The sulphides of group IV cations are not

(b) Complete the following reactions : 2 precipitated in group II. Explain. 2 @ CH, CH, 1 SX,

(b) Calculate the pH of 0.05 M aqueous

(i) CH, CH, MgBr ROH solution of sodium acetate. Given : The pKa of acetic acid is 4.74. 3 11.

(a) What is the product of reaction of an alkene and peracetic acid ? Give Part—II (Marks : 25) mechanism. 3 (Functional Group Organic Chemistry—I)

(b) Complete the following reactions : 2 Note: Attempt any five questions from question है CH, CO CH, +CH) - CH, Ht nos. 8 to 14. @ | | OH OH

Q10.(a) What is the role of aluminium chloride in का Ww ; i,

(i) CH; CHO+NH, OH! Friedel-Craft’s alkylation reaction ? 2 है . stati 12.

(a) Complete and name the following

(b) Discuss the mechanism of nitration of reactions : 2 Benzene. 3 @ (CH), CHOH +1, NaOH

Q11.(a) What reagents are used for the oxidation of OH OH side chain in aromatic hydrocarbons? = 2 Gi) (CH), di _cy (CH,), —H280_,

(b) Name and give structure of oxidation

(b) Arrange the following in increasing order product of

(i) Toluene

(ii) Propyl benzene of solubility in water. Justify your answer :

(ii) 1, 2-dimethyl benzene. 3 8

(i) CHsCHeCH2CHs

Q12.(a) Explain the mechanism of Sy? with the

(i) CHsCH2CH.0H help of an appropriate example. 3

(ii) CHzOHCH.OH [8]

Q13.(a) Discuss Huckel’s rule of aromaticity. Why BCHCT-133 is 1, 3, 5-cycloheptatrienyl cation aromatic

(b) Write equation for the following named . Gi) Wolff-Kishner reduction trinitrophenol, 2 three) : 3 ji) ioe NaOH + CaO

(iii) (OKs NCI + (Op . 500;

(iv) CH,CH,CH,0H 25 . हैं light [10]

Q14.1. 0. 303

(g) = 20;

(g) = 18x10)

Q15.1. 0. ; i i ih

(6) CH, CH, 1 —S®-,

(i) CHsCH,CH,OH Gi) CH, CH, MgBr —B0#_,

(iii) CH2OHCH20H @ Co NaOH + CaO S-™COONa Gi) | OHCH)CH20H + HOOC -<O)- coon -H*, Gii) (O)-i= NCI + (Os

(iv) CH3CH2CH,0H aon, “Oe