
	Trending ▼ ICSE CBSE 10th ISC CBSE 12th CTET GATE UGC NET Vestibulares ResFinder

ISC Class XI Prelims 2025 : Chemistry (City Montessori School (CMS), Kanpur Road, Lucknow)

8 pages, 47 questions, 0 questions with responses, 0 total responses,

Techno Savy
City Montessori School (CMS), Kanpur Road, Lucknow

+Fave Message

Profile Timeline Uploads

Home > apoorvstudy234 > F Also featured on: School Page

Formatting page ...

ANNUAL EXAMINATION 2023-24 Class XI(ISC) CHEMISTRY Paper - I (Theory) Maximum marks: 70 Time: Three hours Instructions: Candidates are allowed additional 15 minules fr onv reading the paper. They must NOT start writing during this time. This paper is divided into four sections -A,B, Cand D. Answer all questions. Section Aconsists ofone question having sub parts ofone mark each. Section B consists often questions of hwo marks each. Section C consists of sevenquestions of three marks each. Section D consists of three questions offive marks each. Cand D. Internalchoices have been provided in oneouestioneach in Sections B,and adjacent to rest o as, sheet same the on done All working, including rough work, should be the answers. The intended marks for questions or parts of questions are given in 1. where they are helpfu. When Balanced equations must be given wherever possible and diagrams shown. solving numerical problems, all essential working must be data: In working out the problems, use the following JK-' motl = 0.0821 L atm K' mot! 8.314 = mot deg cal 1.987 = R constant Gas x 10 IFaraday = 96500 Coulombs. 1Latm =ldm'atm = 101.3J Avogadro 's number = 6.023 SECTION A - 14 MARKS Question 1 those given (A) Fill in the blanks by choosing the appropriate word / words from inthe bracket: [4x1] white, [negative, Lewis acid, positive, Lewis base, basic, acidic, neutral, red, blue, 3, 2, 1, 1.5, 2.5, paramagnetic, diamagnetic, deficiency, excess] (1) For all spontaneous processes, the change in entropy is poSTne whereas change in Gibbs fee energy is a LesAudue to oeaofelectrons. as acts BEs () Terminalalkynes are i L innature and formt a precipitate with (ii) ammonical Silver nitrate solution. (iv) The bond order of Superoxide ion is S-4 |5 .andi is foungud in nature. This paper consists of Eight printed pages. Turn over acdbd (B) Seket and write the correet alternative from the choices given below. Quantum nunbers give complete infommation about the clectron in an |7x1| atom: P: Electrons in motion behave only as waves. Q: s-orbital is non-directional. bones R: An orbital can accomodate a maximum of two electrons with parallel spins. S: The energies of the varioussub-levels in the same shell ofH-atom are in the onder s>p>d>t Which of the above statements are correct? only P &Q (b) only P &R (c) only R & S () only Q & R () The molarity ofa solution obtained by mixing 750 mL of0.S M HCl and 250 mL 2M HCI will be: M 7X05 t 25Dx - 03 (b) 1.00 M (a) 0.0975 M (0.875 M (ii) The species having pyramidalshape is: (a) (c) BF: CH4 (d) 1.75 M (b) HO t NH, (iv) The property which increases with the increase in atomic number in a group is: by Atomic radius (a) lonisation enthalpy (d) Electronegativity (c) Electron gain enthalpy (v) The alkene that exhibits geometrical isomerism is: (b) Propene (a) 2-methylpropene (c) 2-methyl butane (dY But-2-ene S 4 (2) acdbdac (vi) Assertion and Reason lies between the Assertion: The carbon - carbon bond length in Benzene other molecule. bond lengths of C-Cand C =C bonds found in Reason: Benzene exhibits the phenomenon of resonance. and Reason is the correct explanation a Both Assertion and Reason are true of Assertion. Reason is not the correct (b) Both Assertion and Reason are true but explanation of Assertion. (c) Assertion is true but Reason is false. (d) Assertion is false but Reason is true. thermodynamically (vii) Assertion: AIlspontaneous processes are irreversible. entropy. Reason: Inreversible isothermal process,there is no change in correct explanation of (a) Both Assertion and Reason are true and Reason is Assertion. Both Assertion and Reason are true but Reason is not the correct b explanation of Assertion.t sAsertion is true but Reason is false. (d) Assertion is false but Reason is true. questions that follow. (3x1] (C) Read the passage given below carefully and answer the group ofstudents visited Kukrail Picnic Spot. They noticed that Kukrail river, at A the verge of drying, has turmed into a marshy area. During day time they noticed the formation ofbubbles in this area witha foul smell. CHu/methane () Identify the gas which was formed. (ii) What happens when this gas reacts with Cl, is presence of diffused sunlight? (ii) Which mechanism is involved in the above reaction? b Free racholsubzhddr., S-4 (3) Turn over cuyttHC? SECTIONB- 20MARKS Question 2 (2] What type of isomerism is exhibited by the following pair of compounds? CHh-CH,- CH,- NH; andmd (CHI), C H-NH; ckas postan chain CH -CHO () CH,= CH -OH Tastomes mats Question 3 (2] Write the electronic configuration of Chromium (Z =24). (ii) Wite the value of all four quantum numbers of the last electron of Zinc (Z = 30). Question 4 -2 m -2 Give reason for the following: 0 lonic rdis of Ca (2 -20) smallr than K' (2Z= 19) e J( ) Electron gain enthalpies of Be, Nand inert gases are positive. )Stadle. elctun [21 s ecmlarchorg Question 5 2] What is the hybridization of the central atom in H;0, NH, and CH,? Discuss the shape of these covalent compounds. . (sp spay- 2 Question 6 (2] 1.575 g of adibasic acid is present in 250 mL of an aqueous solution. 16 mL of N/18NaOH solution neutralises 20 mL of the acid solution. Calculate the equivalent weight and molar mass of the acid. M=21ly/-74= (283-5y Question 7 Draw the structure of the compounds having the following IUPAC name: (i) But-2-ene-1, 4-dioic acid (ii) m-nitrobenzoic acid S-4 n (4) (2] +e Question & AH [21 Why is the first electron gain enthalpy of Oxygen negative while the second one is positive? [2] Question 9 () Which of the following reaction intermediate is more stable and why? mere edensilgoncarby CH, CH, CH, -CS Or CH, - CH, H (ii)Give a chemical test to distinguish between Ethane and Ethene. 71 pels 12:2520-085 ke Question 10 208-5 litre at 580 K. Chlorine formed 17.75 g of PCl; is heated in a closed vessel of ohe Calculate the K, for the maH mes? equilbrum is 3.337 8. Subal PClse) [2] keeo0529 reaction given below: P s - 2085 PClye + Clh) Question 11 [21 =0-059) from surroundings at (i)) In winter season 15 kg of waterat 17 Cabsorbs 75 J ofheat ((+) 30 C. Calculate the entropy change of the sysem and also gfthe surroundings. OR (ii) Why the entropy of aperfectly crystalline solid at zero K is zero? SECTION C- 21 MARKS Question 12 (Give balanced eauations) (bnreqe) How willyou convert the following: huKs ) Methane to Ethane [3) y (1) Acetylene to Acetaldehyde - H-escH +Heee , eg CHo (i11) Benzene to Glyoxal. S-4 (5) Turn over Ynm Sub=, ns|) Question 13 Agolf ball has a mass of40 g and spccd of45 m/s. If the spced can be measured (3| within inaccuracy of 2%, calculate the uncertainty of position. (h =6.626 x 10 Js) Question 14 (3| Consider the cquilibrium 2NOg t+ Cl) 2NOCI For which AH =-77.07 kJ mol. How will the amount of Cl, at cquilibrium be affected by the following? ) Removal ofNO(g) Ea gtsbnekid. ( ) Ihcreasing the temperature ea: 48es backwboy (ii) Decrease the volume of container. (bothnttel) e4-ge Question 15 [3] Write balanced equations for the following: H-iC-H + () Ethyne reacts with ammonical Silver nitrate solution. (ii) Propyne is passed through 40% H,SO, containing 1% HgSO4 at 333 K. Cu,-(3 CH tH (iii) Propene undergoes addition of Ozone followed by hydrolysis. Question 16 (3] Calculate the enthalpy of formation of Methane from the following data: () Co +Oxg COx8) AH=-394 kJ / mol methd-00 aH=-286kJ/ mol1-26 |el. 2 (i) CHag) + 20x) COxg) + 2H,O0 AH =-890 kJ / mol Question 17 (cns) can Ho-C-n n Draw the optical isomers of CaHO%. (Totuecuid) (i) (2.mby 0.303 gof an organic compound was analysed for Nitrogen by Kjeldahl's method. The Ammonia evolved was absorbed in 50 mL of0.1 N H,SO4. The excess acid required 25 mL of 0.1 NNaOH for neutralization. Calculate the percentage of Nitrogen in the organic compound. w l4 2:5(:557 Be90303 S-4 (6) SECMN D-WARKS Questiun iite te fuUVHCsCT UR Question 20 Balance the following equation by lon-electron () method: 2MnO, +Co,*Mn*+co: [acidic Medium) number method: (i) Balance the following equation by Oxidation (ii) Find the oxidation number of: (a) O in BaO, (c) (b) Crin K,CrO,t6) (d) S in Na,SOs Sin H;S;O, Question 21 () What happens when HBr reacts with Propene in the presence of organic (ii) Give reason for the following: peroxide? Give the equation also. Ch=Ci-Ct t MBr (a) (b) hcu-cy Alkenes are more reactive than alkanes. Benzene is highly unsaturated but does not undergoes addition reaction. (iu) Write the IUPAC name of each of the following organic compounds: (a) En,-En, 3.4,6-bintgotnee. CH H-H H,- CHCH, (C CH,- CH, 2 Q-CH, (b) etybangene Br (c) H,-CH-CH CHH, OH S-4 -C0OH 4-bseme, 5-chlro,g-hdnoxyhexn (8)

Formatting page ...

apoorvstudy234 chat

Horizontal lines at:
Guest Horizontal lines at:
AutoRM Data:
Box geometries: