ENGINEERING CHEMISTRY LABORATORY MANUAL-I & II For Students of First Year B.E/B.Tech (Common to All Branches) As Per the Anna University Syllabus - Regulation 2013. Dr. S. Daisylin Anbu Sujitha, M.Sc., Ph.D., Assistant Professor, Department of Chemistry, Sri Sairam Institute of Technology, West Tambaram, Chennai - 600 044. S. Shanthi, M.Sc., M.Phil., Ph.D., Assistant Professor, Department of Chemistry, Anand Institute of Higher Technology, Kalasalingam Nagar, Chennai - 603 103. No.23/15, ‘O’ 1A-Block, Ground Floor, Agastheir Nagar Extn., Villivakkam, Chennai-600 049. Contact : 9080505073, 9444421457, 9994784517 srimaruthipub@gmail.com (i) No part of this publication may be reproduced or distributed in any form or by means, electronic, mechanical, photocopying, recording, or otherwise stored in a database or retrieval system without the prior written permission of this publishers. Information contained in this work has been obtained by Sri Maruthi Publishers from sources believed to be reliable. However neither Sri Maruthi Publishers nor its authors guarantee the accuracy or completeness of any information published and they shall not be responsible for any errors arising out of this information. This publication aims to supply information but not to be understood as a professional service. © Copyright 2010 by Sri Maruthi Publishers, Chennai. First Edition : July 2010 Revised Edition : July 2011 Revised Edition : July 2012 New Edition : July 2013 Revised Edition : July 2014 Printed in INDIA Engineering Chemistry Laboratory Manual - I & II ISB : 978-93-80757-07-0 Price : Rs. 160/Published by : Sri Maruthi Publishers, Chennai Credits: Team Coordinator : M. Muthukumar, K. Murugan Laser Typesetting : Sri Maruthi Publishers Wrapper designed by : Sri Maruthi Publishers Printed by : Sri Maruthi Offset, Chennai. (ii) PREFACE Authors have great pleasure in presenting the first edition of the book, Engineering Chemistry Laboratory Manual, for B.E/B.Tech degree course of the First Year Engineering Students of Anna University Chennai. The Book deals with both Volumetric analysis and Physical Chemistry Experiments. Before starting the experiments, the students are advised to go through the procedure given in the book atleast once, in order to carry out the experiments with perfect understanding. All the experiments have been carried out in the laboratory and the procedure are found practically verified. Neat Diagrams of various types of apparatus normally used in the Chemistry Laboratory are given at the appropriate place. Suggestions for improving the book are most welcome. - Authors (iii) ACKNOWLEDGEMENT First of all, I thank GOD ALMIGHTY for everything. We express our sincere gratitude to Philanthopist, Kalvivallal Thiru. T.Kalasalingam, Chairman, Seva Ratna Shri K. Shridharan, Secretary, Dr. S. Arivalagi, Director Anand Institute of Higher Technology, Chennai, for their support and encouragement. We extremely thankful to the principal Dr. T.A. Raghavendran for permitting us to write this Lab Manual. We would like to put on record our sincere gratitude to Dr. S. Chokkalingam, HOD Chemistry Department, Anand Institute of Higher Technology, Chennai for giving a valuable suggestion to write this lab manual. We thank our colleagues and friends for their inspirations. We deeply acknowledge our Family Members for their never ending encouragement, moral support and patience on all our endeavors. We wish to thank to Sri Maruthi Publishers for the sustained interest shown by them during the entire work. S. Shanthi (iv) GENERAL INSTRUCTIONS Be punctual. Bring manual, record notebook, calculator etc. Maintain discipline and cleanliness in the laboratory. Handle the apparatus and reagent bottles with almost care. Report, breakage of glasswares to the laboratory Assistant immediately. Keep the reagent bottles in their respective places after use. Do not misplace the stoppers of the bottle. Do not throw waste paper, match - stick, broken glasswares etc., inside the sink; put them into the dust bin. Do not discharge concentrated acid into the sink, dilute it before discharging. In case of accident, inform the faculty immediately Before taking any liquid in the burette or the pipette, these should be rinsed with the liquid. The conical flask should not be rinsed with any liquid. It should simply be washed with distilled water. Read the lower meniscus in case of colourless liquids and the upperone in the case of coloured liquids. The solution should be filled in the burette by means of a funnel which must be removed before titrations. The readings should be entered immediately in the practical note-book and not on some piece of paper. When the experimental is over, wash all the glasswares and handover to the laboratory assistant before you leave the lab. (v) PERIODIC TABLE The periodic table of the chemical elements (also known as the periodic table or periodic table of the elements) is a tabular display of the 118 known chemical elements organized by selected properties of their atomic structures. Elements are presented by increasing atomic number, the number of protons in an atom’s atomic nucleus. While rectangular in general outline, gaps are included in the horizontal rows (known as periods) as needed to keep elements with similar properties together in vertical columns (known as groups), e.g. alkali metals, alkali earths, halogens, noble gases. (vi) ANNA UNIVERSITY SYLLABUS Common to all B.E./B.Tech Degree Students Code : GE6163 L 0 CHEMISTRY LABORATORY-I LIST OF EXPERIMENTS T 0 P 2 C 1 (Any FIVE Experiments) 1. Determination of DO content of water sample by Winkler’s method. 2. Determination of chloride content of water sample by argentometric method 3. Determination of strength of given hydrochloric acid using pH meter 4. Determination of strength of acids in a mixture using conductivity meter 5. Estimation of iron content of the water sample using spectrophotometer (1,10- phenanthroline / thiocyanate method) 6. Determination of molecular weight of polyvinylalcohol using Ostwald viscometer 7. Conductometric titration of strong acid vs strong base TOTAL: 30 PERIODS Code : GE6262 CHEMISTRY LABORATORY -II (Any FIVE Experiments) L 0 T 0 P 2 C 1 1. Determination of alkalinity in water sample 2. Determination of total, temporary & permanent hardness of water by EDTAmethod 3. Estimation of copper content of the given solution by EDTA method 4. Estimation of iron content of the given solution using potentiometer 5. Estimation of sodium present in water using flame photometer 6. Corrosion experiment – weight loss method 7. Conductometric precipitation titration using BaCl2 and Na2SO4 8. Determination of CaO in Cement. TOTAL: 30 PERIODS (vii) (viii) Content Code:GE6163 Sl. No. CHEMISTRY LABORATORY - I Date Page Marks No. Experiment 1. Determination of Do Content of Water Sample by Winkler’s Method. 3 2. Determination of Chloride Content of Water Sample by Argentometric Method. 9 3. Determination of Strength of given Hydrochloric Acid using pH Meter. Determination of Strength of Acids in a Mixture using Conductivity Meter. Determination of IRON of the Water Sample using Spectrophotometer (Using ThioCyanate). 15 6. Determination of Molecular Weight Polyvinylalcohol using Ostwald Viscometer. of 33 7. Conductometric Titration of Strong Acid Vs strong Base. 41 SHORT PROCEDURE 45 4. 5. Code:GE6262 Sl. No. Sign 21 27 CHEMISTRY LABORATORY - II Date Experiment Page Marks No. 1. Estimation of Alkalinity of Water 73 2. Estimation of Hardness of Water by EDTA Method 81 3. Estimation of Copper content of the given solution by EDTA Method 89 4. Estimation of Ferrous Ion by Potentiometric Titration. 95 5. Estimation of Sodium Present in Water using Flame Photometer 101 6. Corrosion Experiment Weight Loss Method 105 7. Conductometric Precipitation Titration (BaCl2 Vs Na2SO4) 109 SHORT PROCEDURE 115 VIVA-VOCE 136 (ix) Sign IMPORTANT TERMS IN VOLUMETRIC ANALYSIS Titration: The process of finding out the volume of one of the solution required to react completely with the definite volume of other solution. Titrant: The Solution of known strength. Titrate: The solution which contains a substance whose strength is to be estimated. Indicator: The substance which indicates the end point of titration is called indicator. The indicator indicates the completion of reaction by change in colour at the end point. eg: Phenolphthalein for acid base titration. Strength: The amount of substance dissolved in one litre of a solution expressed in termed as strength of a solution. Strength of solution can also be expressed in any of the following ways. i. Normality: It is the number of gram equivalents of the substance dissolved per litre of the solution. It is denoted by N. N = Weight of solute per litreof the solution Equivalent weight of the solute ii. Molarity: It is the number of moles of solute per litre of the solution. It is denoted by M. M = Weight of solute per litreof the solution Molecular weight of thesolute (x) iii. Molality: It is the number of moles of the substance dissolved in 1000gm or 1kg of the solvent. It is denoted by m. m = Gramsof solute per kg of thesolvent Molecular weight of thesolute iv. Percentage by weight: It is the weight in grams of a solute present in 100gms of the solution. Percentage weight = Weight of solute ×100 Weight of solute weight of solvent v. Equivalent Weight: The equivalent weight of a substance is defined as the number of parts by weight of it that combine with or displace one part by weight of hydrogen or eight parts by weight of oxygen. Equivalent weight of a metal = Atomic weight Valency Equivalent weight of an acid = Molecular weight of an acid Basicity of an acid = Molecular weight of base Acidity of base Equivalent weight of a base Basicity: It is the number of replacable hydrogen atoms in an acid. (xi) Acidity: It is the number of replacable OH groups in one molecule of a base. Standard Solution: A solution of known concentration is known as standard solution. Equivalent weights of Substances Substances Equivalent Weight Sodium hydroxide 40 Sodium thiosulphate 248.19 Potassium dichromate 49.03 Potassium permanganate 31.60 Hydrochloric acid 36.46 Sulphuric acid 49.04 Nitric acid 63 Acetic acid 60 hhhhh (xii)