{"id":27611,"date":"2020-07-07T20:18:48","date_gmt":"2020-07-07T14:48:48","guid":{"rendered":"https:\/\/kseebsolutions.guru\/?p=27611"},"modified":"2021-07-02T15:07:06","modified_gmt":"2021-07-02T09:37:06","slug":"2nd-puc-chemistry-previous-year-question-paper-june-2018","status":"publish","type":"post","link":"https:\/\/kseebsolutions.guru\/2nd-puc-chemistry-previous-year-question-paper-june-2018\/","title":{"rendered":"2nd PUC Chemistry Previous Year Question Paper June 2018"},"content":{"rendered":"<p>Students can Download 2nd PUC Chemistry Previous Year Question Paper June 2018, Karnataka <a href=\"https:\/\/kseebsolutions.guru\/2nd-puc-chemistry-model-question-papers-with-answers\/\">2nd PUC Chemistry Model Question Papers with Answers<\/a> helps you to revise the complete Karnataka State Board Syllabus and score more marks in your examinations.<\/p>\n<h2>Karnataka 2nd PUC Chemistry Previous Year Question Paper June 2018<\/h2>\n<p>Time: 3:15 Hours<br \/>\nMax. Marks: 70<\/p>\n<p>Instructions<\/p>\n<ul>\n<li>The question paper has four parts A, B, C, and D. All parts are compulsory.<\/li>\n<li>Write balanced chemical equations and draw labeled diagrams wherever required.<\/li>\n<li>Use Jog tables and simple calculators if necessary (Use of scientific calculators is not allowed).<\/li>\n<\/ul>\n<p style=\"text-align: center;\"><span style=\"color: #0000ff;\">Part &#8211; A<\/span><\/p>\n<p><span style=\"color: #0000ff;\">I. Answer all the following questions: (10 \u00d7 1 = 10)<\/span><\/p>\n<p>Question 1.<br \/>\nIn a binary solution, the mole fraction of one component is 0.068. What is the mole fraction of another component?<br \/>\nAnswer:<br \/>\n0.932.<\/p>\n<p>Question 2.<br \/>\nState Henry&#8217;s law.<br \/>\nAnswer:<br \/>\nAt constant temperature, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas present above the surface of the solution.<br \/>\np = K<sub>H<\/sub>. x<br \/>\np: partial pressure of the gas.<br \/>\nx: mole fraction of the gas.<br \/>\nK<sub>H<\/sub>: Henry\u2019s constant.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 3.<br \/>\nWhy does the conductivity of a solution decrease with dilution?<br \/>\nAnswer:<br \/>\nThe number of ions per unit volume that carries the current in a solution decreases.<\/p>\n<p>Question 4.<br \/>\nA chemical reaction has the rate expression, Rate = K[A]<sup>2<\/sup> [B]. What is its overall order?<br \/>\nAnswer:<br \/>\n3.<\/p>\n<p>Question 5.<br \/>\nGive the principle involved in the zone refining process.<br \/>\nAnswer:<br \/>\nThe impurities are more soluble in the melt than in the solid state of the metal.<\/p>\n<p>Question 6.<br \/>\nWhich noble gas does not occur in the atmosphere?<br \/>\nAnswer:<br \/>\nRadon.<\/p>\n<p>Question 7.<br \/>\nWhat is the value of the co-ordination number of Fe in K[Fe(CN)<sub>6<\/sub>]?<br \/>\nAnswer:<br \/>\n6<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 8.<br \/>\nIn aryl halides, what is the hybridization of the carbon atom to which halogen is attached?<br \/>\nAnswer:<br \/>\nSp<sup>2<\/sup>.<\/p>\n<p>Question 9.<br \/>\nWrite the IUPAC name of CH<sub>3<\/sub>COCH<sub>2<\/sub>CH<sub>2<\/sub>CH<sub>3<\/sub>.<br \/>\nAnswer:<br \/>\nPentan-2-one.<\/p>\n<p>Question 10.<br \/>\nName the nitrogen base present only in DNA, not in RNA.<br \/>\nAnswer:<br \/>\nThymine.<\/p>\n<p style=\"text-align: center;\"><span style=\"color: #0000ff;\">Part &#8211; B<\/span><\/p>\n<p><span style=\"color: #0000ff;\">Answer any FIVE questions (Each question carries two marks): (5 \u00d7 2 = 10)<\/span><\/p>\n<p>Question 11.<br \/>\nCalculate the number of particles (atoms) per unit cell in an FCC crystal lattice.<br \/>\nAnswer:<br \/>\nNo. of particles (atoms) in FCC unit cell<br \/>\n= \\(\\frac {1}{8}\\) \u00d7 8 (at corners) + \\(\\frac {1}{2}\\) \u00d7 6 (at faces)<br \/>\n= 1 + 3<br \/>\n= 4 particles.<\/p>\n<p>Question 12.<br \/>\nDraw a neat labeled diagram of H<sub>2<\/sub> &#8211; O<sub>2<\/sub> fuel cell and write overall cell reaction.<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64645\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q12.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q12\" width=\"298\" height=\"207\" \/><br \/>\nIn this cell, hydrogen and oxygen are bubbled through porous carbon electrodes into concentrated aqueous sodium hydroxide.<br \/>\nHydrogen is fed into the anode compartment where it is oxidized.<br \/>\nThe oxygen is fed into the cathode compartment where it is reduced.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64644\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q12.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q12.1\" width=\"371\" height=\"93\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q12.1.png 371w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q12.1-300x75.png 300w\" sizes=\"(max-width: 371px) 100vw, 371px\" \/><\/p>\n<p>Question 13.<br \/>\nThe rate constant of a first-order reaction is 1.15 \u00d7 10<sup>-3<\/sup> s<sup>-1<\/sup>. Calculate its half-life period (t\u00bd).<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64646\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q13.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q13\" width=\"244\" height=\"56\" \/><\/p>\n<p>Question 14.<br \/>\nGive reason:<\/p>\n<ol>\n<li>What is lanthanoid contraction?<\/li>\n<li>Which is the general oxidation state shown by actinoids?<\/li>\n<\/ol>\n<p>Answer:<\/p>\n<ol>\n<li>Radii of members of 3 transition series are very much similar to corresponding members of 2 series.<\/li>\n<li>Very difficult to separate lanthanoids of 2 series elements from 3rd series elements in the pure state during extraction.<\/li>\n<\/ol>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 15.<br \/>\nHow does phenol react with cone, nitric acid? Give an equation.<br \/>\nAnswer:<br \/>\n(i) With dilute nitric acid at low temperature (298 K) phenol yields a mixture of ortho and para nitrophenols.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64648\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q15.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q15\" width=\"325\" height=\"151\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q15.png 325w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q15-300x139.png 300w\" sizes=\"(max-width: 325px) 100vw, 325px\" \/><br \/>\n(ii) With Conc. nitric acid phenol is converted to 2, 4, 6-trinitrophenol (picric acid).<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64647\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q15.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q15.1\" width=\"291\" height=\"161\" \/><\/p>\n<p>Question 16.<br \/>\nExplain Cannizzaro&#8217;s reaction to an example.<br \/>\nAnswer:<br \/>\nAldehydes which do not have an \u03b1-hydrogen atom, undergo self-oxidation and reduction reaction on heating with conc. alkali. In this reaction, one molecule of the aldehyde is reduced to alcohol while another is oxidized to carboxylic acid salt.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64649\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q16.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q16\" width=\"440\" height=\"182\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q16.png 440w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q16-300x124.png 300w\" sizes=\"(max-width: 440px) 100vw, 440px\" \/><\/p>\n<p>Question 17.<br \/>\nWhat are analgesics? Give one example for non-narcotic analgesics.<br \/>\nAnswer:<br \/>\nAnalgesics are chemicals used to reduce body pain without causing impairment of consciousness.<br \/>\nEx: Non-norcotic analgesic &#8211; Aspirin;<br \/>\nNorcotic analgesic &#8211; Morphine.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 18.<br \/>\nWhat is saponification? Give the equation to form sodium stearate by this method.<br \/>\nAnswer:<br \/>\nSoap is prepared by a heating aqueous solution of potassium or sodium hydroxide with fat or oil. This reaction is called saponification.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64650\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q18.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q18\" width=\"559\" height=\"135\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q18.png 559w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q18-300x72.png 300w\" sizes=\"(max-width: 559px) 100vw, 559px\" \/><\/p>\n<p style=\"text-align: center;\"><span style=\"color: #0000ff;\">Part &#8211; C<\/span><\/p>\n<p><span style=\"color: #0000ff;\">Answer any FIVE of the following (Each question carries three marks): (5 \u00d7 3 = 15)<\/span><\/p>\n<p>Question 19.<br \/>\nDraw a neat labeled diagram of electrolytic cells used in the extraction of Aluminium by the Hall-Heroult process. Write the reactions that take place at cathode and anode.<br \/>\nAnswer:<br \/>\nPurified alumina is fused with cryolite and fluorspar which lowers the melting point of the alumina. The fused mass is taken in steel vessels lined with carbon lining acts as a cathode. Bunch of carbon rods dipped in the molten solution acts as an anode.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64651\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q19.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q19\" width=\"374\" height=\"259\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q19.png 374w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q19-300x208.png 300w\" sizes=\"(max-width: 374px) 100vw, 374px\" \/><br \/>\nOn electrolysis aluminum is discharged at cathode and oxygen is liberated at the anode which reacts with the carbon of the anode a producing CO and CO<sub>2<\/sub>.<br \/>\nThe electrolytic reactions are:<br \/>\nCathode: Al<sup>3+<\/sup> + 3e<sup>&#8211;<\/sup> \u2192 Al<br \/>\nAnode: C + O<sup>2-<\/sup> \u2192 CO + 2e<sup>&#8211;<\/sup><br \/>\nC + 2O<sup>2-<\/sup> \u2192 CO<sub>2<\/sub> + 4e<sup>&#8211;<\/sup><\/p>\n<p>Question 20.<br \/>\nWrite the equations with conditions for the manufacture of nitric acid by Ostwald&#8217;s process.<br \/>\nAnswer:<br \/>\nStep 1: Catalytic oxidation of ammonia gives nitric oxide.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64653\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q20.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q20\" width=\"313\" height=\"50\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q20.png 313w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q20-300x48.png 300w\" sizes=\"(max-width: 313px) 100vw, 313px\" \/><br \/>\nStep 2: Nitric oxide thus formed combines with oxygen gives NO<sub>2<\/sub><br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64652\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q20.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q20.1\" width=\"193\" height=\"40\" \/><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64663\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q24.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q24\" width=\"277\" height=\"32\" \/><br \/>\nStep 3: Nitrogen dioxide so formed diso1ves in water to give HNO<sub>3<\/sub><br \/>\nH<sub>2<\/sub>O + 3NO<sub>2<\/sub> \u2192 2HNO<sub>3<\/sub> + NO<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 21.<br \/>\nComplete the following equations:<br \/>\n(i) SO<sub>2<\/sub> + Cl<sub>2<\/sub> \\(\\underrightarrow { charcoal }\\) ____<br \/>\n(ii) S + 2H<sub>2<\/sub>SO<sub>4<\/sub> \u2192 _____<br \/>\n(iii) NO + O<sub>3<\/sub>(conc.) \u2192 _____<br \/>\nAnswer:<br \/>\n(i) SO<sub>2<\/sub> + Cl<sub>2<\/sub> \\(\\underrightarrow { charcoal }\\) SO<sub>2<\/sub>Cl<sub>2<\/sub> (Sulphuryl Chloride)<br \/>\n(ii) S + 2H<sub>2<\/sub>SO<sub>4<\/sub> \u2192 2H<sub>2<\/sub>O + 3SO<sub>2<\/sub><br \/>\n(iii) NO + O<sub>3<\/sub> \u2192 NO<sub>2<\/sub> + O<sub>2<\/sub><\/p>\n<p>Question 22.<br \/>\n(a) Write any two anomalous properties of fluorine. (2)<br \/>\nAnswer:<br \/>\nThe anomalous behavior of fluorine is due to its<\/p>\n<ul>\n<li>Smaller size.<\/li>\n<li>Highest electronegativity.<\/li>\n<li>Low F \u2014 F bond dissociation enthalpy.<\/li>\n<li>Non-availability of d-orbitals in the valence shell.<\/li>\n<\/ul>\n<p>(b) Give an equation for the reaction of chlorine with hydrogen sulphide. (1)<br \/>\nAnswer:<br \/>\nIt reacts with the compounds containing hydrogen to form HCl.<br \/>\nH<sub>2<\/sub> + Cl<sub>2<\/sub> \u2192 2HCl<br \/>\nH<sub>2<\/sub>S + Cl<sub>2<\/sub> \u2192 2HCl + S<br \/>\nC<sub>10<\/sub>H<sub>16<\/sub> + 8Cl<sub>2<\/sub> \u2192 16HCl + 10C<\/p>\n<p>Question 23.<br \/>\n(a) Transition metals show catalytic property: Give reasons. (2)<br \/>\nAnswer:<br \/>\nInterstitial compounds are those which are formed by transitional element. when small atoms like H, C, and N are trapped inside the crystal lattices of metals.<br \/>\nExample: VH<sub>0.5<\/sub><\/p>\n<p>(b) Between \\(\\mathbf{C u}_{(\\mathbf{a q})}^{\\mathbf{2 +}}\\) and \\(\\mathbf{C u}_{(\\mathbf{a q})}^{+}\\) which is more stable? (1)<br \/>\nAnswer:<br \/>\nCu<sup>2+<\/sup><\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 24.<br \/>\nWrite the balanced equations in the manufacture of potassium dichromate from chromite ore.<br \/>\nAnswer:<br \/>\nThe chromate and dichromates are interconvertible in aqueous solutions depending upon the pH of the solution.<br \/>\nAt low pH (acidic medium):<br \/>\nChromate converts into dichromate<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64663\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q24.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q24\" width=\"277\" height=\"32\" \/><br \/>\nAt high pH (alkaline medium):<br \/>\ndichromate is converted into chromate<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64662\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q24.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q24.1\" width=\"269\" height=\"32\" \/><\/p>\n<p>Question 25.<br \/>\nExplain the hybridization, geometry, and magnetic property of [CoF6]3- ion on the basis of the Valence Bond Theory (Atomic number of Co = 27).<br \/>\nAnswer:<br \/>\n(i) Orbitals of Co<sup>3+<\/sup> ion<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64667\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q25\" width=\"359\" height=\"58\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.png 359w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25-300x48.png 300w\" sizes=\"(max-width: 359px) 100vw, 359px\" \/><br \/>\n(ii) In Co<sup>3+<\/sup> ion sp<sup>3<\/sup>d<sup>2<\/sup> hybridization takes place d<sup>2<\/sup> hybridized orbitals of Co<sup>3+<\/sup><br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64664\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q25.1\" width=\"390\" height=\"66\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.1.png 390w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.1-300x51.png 300w\" sizes=\"(max-width: 390px) 100vw, 390px\" \/><br \/>\n(iii) Six pairs of electrons, one from each F- ion occupy the six hybrid orbitals. Thus, the complex has octahedral geometry and paramagnetic in nature due to the presence of four unpaired electrons.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64666\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.2.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q25.2\" width=\"473\" height=\"66\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.2.png 473w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q25.2-300x42.png 300w\" sizes=\"(max-width: 473px) 100vw, 473px\" \/><br \/>\nFor [CoF<sub>6<\/sub>]<sup>3-<\/sup> Complex:<\/p>\n<ul>\n<li>Type of hybridisation: sp<sup>3<\/sup>d<sup>2<\/sup><\/li>\n<li>Geometry: Octahedral<\/li>\n<li>Magnetic property: Parainagnetic.<\/li>\n<\/ul>\n<p>Question 26.<br \/>\n(a) What is an ambidentate ligand? Name the type of structural isomerism arises when such ligand present in the complex.<br \/>\nAnswer:<br \/>\nLigand which can ligate through two different atoms is called ambidentate ligand.<br \/>\nLinkage isomerism.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>(b) Write the IUPAC name of K<sub>2<\/sub>[Zn(OH)<sub>4<\/sub>].<br \/>\nAnswer:<br \/>\nK<sub>2<\/sub>[Zn(OH)<sub>4<\/sub>] &#8211; Potassium tetrahydraxidozincate(II)<\/p>\n<p style=\"text-align: center;\"><span style=\"color: #0000ff;\">Part &#8211; D<\/span><\/p>\n<p><span style=\"color: #0000ff;\">IV. Answer any three of the following (Each question carries five marks): (3 \u00d7 5 = 15)<\/span><\/p>\n<p>Question 27.<br \/>\n(a) Calculate the packing efficiency in a body-centered cubic lattice.<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64670\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q27a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q27(a)\" width=\"186\" height=\"177\" \/><br \/>\nFrom the figure, it is clear that the atom at the center will be in touch with the other two atoms along the body diagonal.<br \/>\nLet a: be the edge length of the cube<br \/>\nb: be the face diagonal<br \/>\nc: be the body diagonal<br \/>\nr: is the radius of the sphere and c = 4r<br \/>\nIn \u2206EFD<br \/>\nb<sup>2<\/sup> = a<sup>2<\/sup> + a<sup>2<\/sup><br \/>\nb<sup>2<\/sup> = 2a<sup>2<\/sup><br \/>\nIn \u2206AFD<br \/>\nc<sup>2<\/sup> = a<sup>2<\/sup> + b<sup>2<\/sup><br \/>\nc<sup>2<\/sup> = a<sup>2<\/sup> + 2a<sup>2<\/sup> = 3a<sup>2<\/sup><br \/>\nc = \u221a3 \u00d7 a<br \/>\n4r = \u221a3 \u00d7 a<br \/>\na = \\(\\frac{4 r}{\\sqrt{3}}\\)<br \/>\nVolume of the cube = \\(a^{3}=\\left(\\frac{4}{\\sqrt{3}} r\\right)^{3}\\)<br \/>\nIn this unit cell, total number of particles is 2 and volume is 2 \u00d7 \\(\\frac{4}{3} \\pi r^{3}\\)<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64668\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q27a.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q27(a).1\" width=\"465\" height=\"158\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q27a.1.png 465w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q27a.1-300x102.png 300w\" sizes=\"(max-width: 465px) 100vw, 465px\" \/><br \/>\nPacking efficiency = 68%<\/p>\n<p>(b) What is a Schottky defect?<br \/>\nAnswer:<br \/>\nIt is a type of defect that arises in ionic solids in which an equal number of cations and anions are missing from their lattice points. This defect decreases the density of the ionic solid.<\/p>\n<p>Question 28.<br \/>\n(a) 5.8g of non-volatile, non-electrolyte solute was dissolved in 100 g of carbon disulphide (CS<sub>2<\/sub>). The vapor pressure of the solution was found to be 190 mm of Hg. Calculate the molar mass of the solute.<br \/>\nGiven: Vapour pressure of pure CS is 195 mm of Hg and the molar mass of CS<sub>2<\/sub> is 76g\/mol.<br \/>\nAnswer:<br \/>\nData: Vapour pressure of solvent = P<sub>0<\/sub> = 195mm<br \/>\nVapour pressure of solution = P = 190 mm<br \/>\nP<sub>0<\/sub> &#8211; P = 195 &#8211; 190 = 5 mm<br \/>\nRelative lowering of vapour pressure = \\(\\frac{P^{\\circ}-P}{P}=\\frac{5}{195}\\) = 0.02564<br \/>\nMass of solute in grams = W<sub>2<\/sub> = 5.8g<br \/>\nMass of solvent (CS<sub>2<\/sub>) in grams = 100g<br \/>\nMolar mass of solvent (CS<sub>2<\/sub>) = 76g mol<sup>-1<\/sup><br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64671\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q28a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q28(a)\" width=\"275\" height=\"151\" \/><\/p>\n<p>(b) Mention any two differences between ideal and non-ideal solutions.<br \/>\nAnswer:<br \/>\nThe ideal solution<br \/>\n(i) Obey\u2019s Raoult&#8217;s law over the entire range of concentration.<br \/>\n(ii) There is no change in enthalpy when the solution is formed from its components.<br \/>\n\u0394H<sub>max<\/sub> = 0<br \/>\n(iii) There is no change in volume when the solution is formed from its components.<br \/>\n\u0394V<sub>max<\/sub> = 0<br \/>\n(iv) The interactions between the components in solution are similar to those in the pure components.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Non-ideal solution<br \/>\n(i) Does not obey Raoult\u2019s law over the entire range of concentration.<br \/>\n(ii) There is a change in enthalpy when the solution is formed from its components.<br \/>\n\u0394H<sub>max<\/sub> \u2260 0<br \/>\n(iii) There is a change in volume when the solution is formed from its components.<br \/>\n\u0394V<sub>max<\/sub> \u2260 0<br \/>\n(iv) The interaction between the components in solution is different from those of the pure components.<\/p>\n<p>Question 29.<br \/>\n(a) Calculate e.m.f of the cell in which the following reaction takes place:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64735\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q29a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q29(a)\" width=\"255\" height=\"94\" \/><br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64672\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q29a.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q29(a).1\" width=\"209\" height=\"76\" \/><br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64674\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q29a.2.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q29(a).2\" width=\"229\" height=\"100\" \/><\/p>\n<p>(b) State the Faraday&#8217;s first law of electrolysis. How many Faraday of electricity is required for the reduction of 1 mole of Mg<sup>2+<\/sup> ions?<br \/>\nAnswer:<br \/>\nDuring electrolysis, the amount of any substance deposited or liberated at an electrode is directly proportional to the quantity of electricity passed through the electrolytic solution.<br \/>\nW = ZQ; Q = It<br \/>\nW = ZIt<br \/>\nW \u2192 Mass of substance discharged at an electrode.<br \/>\nZ \u2192 Electrochemical equivalent.<br \/>\nI \u2192 Electric current in amperes.<br \/>\nt \u2192 Time in seconds.<br \/>\n2 Faraday&#8217;s of electricity is required.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 30.<br \/>\n(a) Derive an integrated rate equation for the rate constant of a zero-order reaction.<br \/>\nAnswer:<br \/>\nConsider a zero-order reaction.<br \/>\nR \u2192 P<br \/>\nRate = \\(\\frac{-d[R]}{d t}\\) = k[R]<sup>0<\/sup><br \/>\nwhere k is rate constant for zero order reaction.<br \/>\n\\(\\frac{-d[R]}{d t}\\) = k<br \/>\nd[R] = -k.dt<br \/>\nIntegrating both sides<br \/>\n\u222bd[R] = -\u222bk.dt<br \/>\n[R] = -kt + I &#8230;.. (1)<br \/>\nI is constant in integration.<br \/>\nAt t = 0, [R] = [R]<sub>0<\/sub><br \/>\nwhere [R]<sub>0<\/sub> is initial concentration of the reactant.<br \/>\nSubstituting in equation (1)<br \/>\n[R]<sub>0<\/sub> = -k \u00d7 0 + I<br \/>\nI = [R]<sub>0<\/sub><br \/>\nSubstituting I value in equation (1)<br \/>\n[R] = -kt + [R]<sub>0<\/sub><br \/>\n\\(k=\\frac{[R]_{0}-[R]}{t}\\)<\/p>\n<p>(b) Draw a graph showing effect of catalyst on the activation energy of a chemical reaction.<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64737\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q30b.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q30(b)\" width=\"347\" height=\"216\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q30b.png 347w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q30b-300x187.png 300w\" sizes=\"(max-width: 347px) 100vw, 347px\" \/><br \/>\nCatalyst provides an alternate pathway by reducing the activation energy and lowering the energy barrier. More molecules enter the threshold energy state leading to chemical reaction and hence increases the rate.<\/p>\n<p>Question 31.<br \/>\n(a) Write any two characteristics of chemical adsorption.<br \/>\nAnswer:<br \/>\nWhen the molecules of the adsorbate are held to the surface of the adsorbent by the chemical bonds, the adsorption is called chemical adsorption or chemisorption.<br \/>\nCharacteristics:<\/p>\n<ul>\n<li>It is specific in nature.<\/li>\n<li>It is irreversible in nature.<\/li>\n<li>Adsorption increases as temperature increases.<\/li>\n<\/ul>\n<p>(b) What is the Brownian movement? What is the cause of it?<br \/>\nAnswer:<br \/>\nIn the dispersion medium, colloidal particles are in continuous zig random motion in all directions. This type of kinetic motion of the colloidal particles is called the Brownian movement.<br \/>\nBrownian movement is due to the bombardment between the colloidal particles and the particles of the dispersion medium.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>(c) What is homogeneous catalysis?<br \/>\nAnswer:<br \/>\nA catalytic process in which reactant and the catalyst are in the same phase, then the process is called homogeneous catalysis.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64738\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q31c.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q31(c)\" width=\"506\" height=\"230\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q31c.png 506w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q31c-300x136.png 300w\" sizes=\"(max-width: 506px) 100vw, 506px\" \/><\/p>\n<p><span style=\"color: #0000ff;\">V. Answer any four of the following (Each question carries five marks): (4 \u00d7 5 = 20)<\/span><\/p>\n<p>Question 32.<br \/>\n(a) Write equations for the steps in the S<sub>N<\/sub>1 mechanism of conversion of tertiary butyl bromide into tertiary butyl alcohol.<br \/>\nAnswer:<br \/>\nThe reaction between tert-butyl bromide and hydroxide ion gives tert-butyl alcohol. The rate of reaction depends only on the concentration of tert-butyl bromide. Hence it is a nucleophilic first order substitution reaction.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64742\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q32(a)\" width=\"347\" height=\"107\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.png 347w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a-300x93.png 300w\" sizes=\"(max-width: 347px) 100vw, 347px\" \/><br \/>\nMechanism:<br \/>\nStep 1: Polarised C \u2014 Br undergoes cleavage to produce planar carbocation.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64739\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q32(a).1\" width=\"308\" height=\"109\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.1.png 308w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.1-300x106.png 300w\" sizes=\"(max-width: 308px) 100vw, 308px\" \/><br \/>\nStep 2: The carbocation is then attacked by a nucleophile (OH<sup>&#8211;<\/sup>) on either side<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64740\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.2.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q32(a).2\" width=\"307\" height=\"101\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.2.png 307w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32a.2-300x99.png 300w\" sizes=\"(max-width: 307px) 100vw, 307px\" \/><\/p>\n<p>(b) Explain the Wurtz-Fittig reaction with the equation.<br \/>\nAnswer:<br \/>\nA mixture of an alkyl halide and aryl halide gives an alkyl arene when treated with sodium in dry ether.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64743\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32b.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q32(b)\" width=\"411\" height=\"170\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32b.png 411w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q32b-300x124.png 300w\" sizes=\"(max-width: 411px) 100vw, 411px\" \/><\/p>\n<p>(c) CH<sub>3<\/sub>Cl + Nal \\(\\underrightarrow { Acetone }\\) CH<sub>3<\/sub>l + NaCl. Name the above reaction.<br \/>\nAnswer:<br \/>\nFinkelstein Reaction<\/p>\n<p>Question 33.<br \/>\n(a) Write the mechanism of acid-catalyzed dehydration of ethanol to ethene.<br \/>\nAnswer:<br \/>\nStep 1: Formation of protonated alcohol<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64746\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q33(a)\" width=\"348\" height=\"97\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33a.png 348w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33a-300x84.png 300w\" sizes=\"(max-width: 348px) 100vw, 348px\" \/><br \/>\nStep 2: Formation of carbocation<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64744\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33a.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q33(a).1\" width=\"298\" height=\"86\" \/><br \/>\nStep 3: Formation of ethene by the elimination of a proton<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64745\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33a.2.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q33(a).2\" width=\"242\" height=\"105\" \/><\/p>\n<p>(b) How does anisole react with bromine in ethanoic acid? Give equation.<br \/>\nAnswer:<br \/>\nAnisole undergoes bromination with bromine in ethanoic acid to form orthobromoanisole and para-bromoanisole.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64747\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33b.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q33(b)\" width=\"440\" height=\"195\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33b.png 440w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q33b-300x133.png 300w\" sizes=\"(max-width: 440px) 100vw, 440px\" \/><\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 34.<br \/>\n(a) Complete the following equations:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64749\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34ai.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(i)\" width=\"205\" height=\"69\" \/><br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64748\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34ai.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(i).1\" width=\"62\" height=\"44\" \/><\/p>\n<p><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64751\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34aii.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(ii)\" width=\"218\" height=\"70\" \/><br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64750\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34aii.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(ii).1\" width=\"136\" height=\"74\" \/><\/p>\n<p><img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64753\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34aiii.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(iii)\" width=\"240\" height=\"34\" \/><br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64752\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34aiii.1.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(a)(iii).1\" width=\"278\" height=\"33\" \/><\/p>\n<p>(b) Explain the esterification reaction with an example.<br \/>\nAnswer:<br \/>\nAlcohols react with carboxylic acids, in the presence of Conc. H<sub>2<\/sub>SO<sub>4<\/sub> to form esters. This reaction is known as esterification.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64754\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34b.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q34(b)\" width=\"386\" height=\"97\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34b.png 386w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q34b-300x75.png 300w\" sizes=\"(max-width: 386px) 100vw, 386px\" \/><\/p>\n<p>Question 35.<br \/>\n(a) How is methenamine prepared by Hoffmann bromamide degradation reaction? Give equation.<br \/>\nAnswer:<br \/>\nWhen ethanamide (acetamide) is treated with bromine in an aqueous solution of sodium hydroxide, methylamine is obtained.<br \/>\nCH<sub>3<\/sub>CONH<sub>2<\/sub> + Br<sub>2<\/sub> + 4NaOH \u2192 CH<sub>3<\/sub>NH<sub>2<\/sub> + 2NaBr + 2H<sub>2<\/sub>O + Na<sub>2<\/sub>CO<sub>3<\/sub><\/p>\n<p>(b) How is aniline converted to Benzene diazonium chloride? Give equation.<br \/>\nAnswer:<br \/>\nThe conversion of primary aromatic amines into diazonium salts is known as diazotization.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64755\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q35b.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q35(b)\" width=\"515\" height=\"39\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q35b.png 515w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q35b-300x23.png 300w\" sizes=\"(max-width: 515px) 100vw, 515px\" \/><\/p>\n<p>(c) Between ammonia and aniline, which is more basic?<br \/>\nAnswer:<br \/>\nAmmonia.<\/p>\n<p>Question 36.<br \/>\n(a) Write the Haworth structure of Maltose.<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64756\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q36a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q36(a)\" width=\"402\" height=\"151\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q36a.png 402w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q36a-300x113.png 300w\" sizes=\"(max-width: 402px) 100vw, 402px\" \/><\/p>\n<p>(b) What are non-essential amino acids? Name naturally occurring a-amino acid which is not optically active.<br \/>\nAnswer:<br \/>\nAmino acids that are synthesized in the body are known as non-essential amino acids.<br \/>\nExample: Glycine, Alanine.<br \/>\nAmino acids that are not synthesized in the body and must be supplied through the diet are known as essential amino acids.<br \/>\nExample: Lysine, Histidine.<br \/>\nGlycine<\/p>\n<p>(c) Which vitamin deficiency causes the disease &#8216;scurvy&#8217;?<br \/>\nAnswer:<br \/>\nVitamin C.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2019\/11\/KSEEB-Solutions.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018\" width=\"172\" height=\"16\" \/><\/p>\n<p>Question 37.<br \/>\n(a) How is nylon 6, 6 prepared? Give equation.<br \/>\nAnswer:<br \/>\nIt is obtained by the condensation polymerization of hexamethylene diamine with adipic acid under high pressure and at high temperature.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64774\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q37a.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q37(a)\" width=\"637\" height=\"63\" srcset=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q37a.png 637w, https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q37a-300x30.png 300w\" sizes=\"(max-width: 637px) 100vw, 637px\" \/><\/p>\n<p>(b) Write the partial structure of<br \/>\n(i) Polythene<br \/>\nAnswer:<br \/>\n[- CH<sub>2<\/sub> &#8211; CH<sub>2<\/sub> -]<sub>n<\/sub><\/p>\n<p>(ii) Neoprene.<br \/>\nAnswer:<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-64775\" src=\"https:\/\/kseebsolutions.guru\/wp-content\/uploads\/2020\/07\/2nd-PUC-Chemistry-Previous-Year-Question-Paper-June-2018-Q37bii.png\" alt=\"2nd PUC Chemistry Previous Year Question Paper June 2018 Q37(b)(ii)\" width=\"171\" height=\"75\" \/><\/p>\n<p>(c) Name the monomer present in natural rubber.<br \/>\nAnswer:<br \/>\nIsoprene.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Students can Download 2nd PUC Chemistry Previous Year Question Paper June 2018, Karnataka 2nd PUC Chemistry Model Question Papers with Answers helps you to revise the complete Karnataka State Board Syllabus and score more marks in your examinations. Karnataka 2nd PUC Chemistry Previous Year Question Paper June 2018 Time: 3:15 Hours Max. Marks: 70 Instructions &hellip;<\/p>\n","protected":false},"author":5,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[82],"tags":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts\/27611"}],"collection":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/comments?post=27611"}],"version-history":[{"count":0,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/posts\/27611\/revisions"}],"wp:attachment":[{"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/media?parent=27611"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/categories?post=27611"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kseebsolutions.guru\/wp-json\/wp\/v2\/tags?post=27611"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}