Chemistry Paper 3, May-June 2017/title> <link href="../Maincss.css" rel="stylesheet" type="text/css" />     </head> <body ondragstart="return false" onselectstart="return false"> <div class="grid-container"> <div class="header"><img src="../images/waechead.png" /> </div><br /><br /> <div class="menuButton" onclick="myFunction(this)" id="menuToggle"> <div class="bar1"></div> <div class="bar2"></div> <div class="bar3"></div> </div> <nav class="menu" id="example"> <ul> <li style="color:#000;"><a href="../index.htm">Index <span><strong style="color:transparent;">▾</strong></span></a></li> <li class="current"> <a href="#">Language <strong>▾</strong></a> <ul> <li><a href="../Arabic/Arabmain.html">Arabic</a></li> <li><a href="../Edo/Edomain.html">Edo</a></li> <li><a href="../Efik/Efikmain.html">Efik</a></li> <li><a href="../English/Englmain.html">English Language</a></li> <li><a href="../French/Frechmain.html">French</a></li> <li><a href="../Hausa/Hausamain.html">Hausa</a></li> <li><a href="../Ibibio/Ibibiomain.html">Ibibio</a></li> <li><a href="../Igbo/Igbomain.html">Igbo</a></li> <li><a href="../Literature/litEmain.html">Lit-In-English</a></li> <li><a href="../Yoruba/Yormain.html">Yoruba</a></li> </ul> </li> <li> <a href="#">General <strong>▾</strong></a> <ul> <li><a href="../Civic/Civicmain.html">Civic Education</a></li> <li><a href="../CRK/CRSmain.html">Christian Religious Studies</a></li> <li><a href="../Dyeing/Dyemain.html">Dyeing & Bleaching</a></li> <li><a href="../Economics/Econsmain.html">Economics</a></li> <li><a href="../Geography/Geomain.html">Geography</a></li> <li><a href="../Government/Govtmain.html">Government</a></li> <li><a href="../History/histmain.html">History</a></li> <li><a href="../Islamic/IRKmain.html">Islamic Studies</a></li> <li><a href="../Leather/Leathermain.html">Leather Goods Manufacturing & Repairs</a></li> <li><a href="../Mining/Miningmain.html">Mining</a></li> <li><a href="../Music/Musicmain.html">Music</a></li> <li><a href="../Painting/Paintmain.html">Painting & Decorating</a></li> <li><a href="../Photography/Photomain.html">Photography</a></li> <li><a href="../Tourism/Tourmain.html">Tourism</a></li> <li><a href="../Visual/VArtmain.html">Visual Art</a></li> </ul> </li> <li> <a href="#">Business <strong>▾</strong></a> <ul> <li><a href="../Automobile/Automobmain.html">Automobile Parts Merchandising</a></li> <li><a href="../BookKeeping/Bookmain.html">Book Keeping</a></li> <li><a href="../Commerce/Commmain.html">Commerce</a></li> <li><a href="../Financial/FAmain.html">Financial Accounting</a></li> <li><a href="../Insurance/Insuremain.html">Insurance</a></li> <li><a href="../Marketing/Marketmain.html">Marketing</a></li> <li><a href="../Office/Officemain.html">Office Practice</a></li> <li><a href="../Salesmanship/Salesmain.html">Salesmanship</a></li> <li><a href="../Shorthand/shortmain.html">Shorthand</a></li> <li><a href="../Storkeeping/Storemain.html">Store Keeping</a></li> <li><a href="../Storemanagement/Storemanmain.html">Store Management</a></li> <li><a href="../Type/Typemain.html">Typewriting</a></li> </ul> </li> <li> <a href="#">Science <strong>▾</strong></a> <ul> <li><a href="../Agriculture/Agricmain.html">Agricultural Science</a></li> <li><a href="../AHusbandry/AHusbandrymain.html">Animal Husbandry</a></li> <li><a href="../Biology/Biomain.html">Biology</a></li> <li><a href="chemmain.html">Chemistry</a></li> <li><a href="../ElectInstallation/EInstallmain.html">Elect Installation & Maintenance Work</a></li> <li><a href="../Fisheries/Fishmain.html">Fisheries</a></li> <li><a href="../Health/HScmain.html">Health Education</a></li> <li><a href="../Physical/PhEdmain.html">Physical Education</a></li> <li><a href="../Physics/physmain.html">Physics</a></li> </ul> </li> <li> <a href="#">Mathematics And Applied Science <strong>▾</strong></a> <ul> <li><a href="../AutoElectrical/AutoElectmain.html">Auto Electrical Works</a></li> <li><a href="../Applied/Applmain.html">Basic Electricity</a></li> <li><a href="../Electronics/electmain.html">Basic Electronics</a></li> <li><a href="../Computer/Compmain.html">Computer Studies</a></li> <li><a href="../DataProcessing/Datapmain.html">Data Processing</a></li> <li><a href="../Further/Furthmain.html">Further Mathematics</a></li> <li><a href="../GSM/GSMmain.html">GSM Phone Maintenance & Repair</a></li> <li><a href="../Mathematics/mathsmain.html">General Mathematics</a></li> <li><a href="../Radio/Radiomain.html">Radio,TV & Electr. 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A formation of yellow precipitate indicates ethanol , if no yellow precipitate / no visible reaction, it indicates propan-I-ol. <br /> (ii) <u>ethene and ethyne</u> To a portion of each sample add Tollen’s reagent / (Ammoniacal silver trioxonitrate (V) ) solution / Ammoniacal copper I chloride solution . White / red precipitate indicates ethyne, if no precipitate then it indicates the presence of ethane .</p> <p> <br /> (b) (i) The acid HNO3 reacts / oxidizes KMnO4 / HNO3 is a stronger oxidizing agent<br /> (ii) To avoid / prevent it from being oxidized by air to (Fe2(SO4)3). <br /> (iii) To prevent Na metal from reacting with oxygen and moisture in air <br /> (iv) The alkalis will react with glass-stopper and seal the stopper of the reagent bottle</p> </div> <div style="text-align:center;width:100%;padding:5px ;"> <input name="Submit" type="submit" class="button" id="Reset" value="Prev" onclick="window.location.href='../Chemistry/chem326mq2B.html'" /> </div> </div> </div> <div class="footer"> Copyright © 2018. The West African Examinations Council. All rights reserved. <br /> <a href="#" target="_blank"> Powered by Sidmach Technologies (Nigeria) Limited.</a> </div> </div> </body> </html>