physical chemistry lab manual
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DESCRIPTIONPhysical Chemistry Lab Manual for student
FOUNDATION IN SCIENCETRIMESTER 1
UNIVERSITI TUNKU ABDUL RAHMANCENTRE FOR FOUNDATION STUDIES
Table of content:
Lab Title Page
1 Introduction to laboratory safety and apparatus 1
2 Precipitation of barium (II) sulphate 7
3 Determination of the amount of dissolved oxygen in a water sample byiodometry The Winklers method 8
4 Gases Boyles Law and Charless Law 11
5 Thermochemistry Determination of heat of neutralization ofhydrochloric acid by sodium hydroxide 14
6 Reaction kinetics Determination of the activation energy of the reactionbetween oxalic acid and potassium permanganate 19
7 Rate law of an iodine clock reaction 21
8 Determination of pKa of Bromocresol Green 25
9 Determination of the percentages of sodium carbonate and sodiumhydroxide in a mixture 28
10 Ionic Measurement of the conductivities of strong and weak electrolytes 30
UNIVERSITI TUNKU ABDUL RAHMANCENTRE OF FOUNDATION STUDIES
LABORATORY SAFETY RULES
The following rules must be obeyed by all students in the science laboratory of the faculty. Willful orrepeated inadvertent noncompliance may result in dismissal or suspension from the laboratories.
I. No entry without permission:i) Outsiders are not allowed to enter the laboratory without permission.ii) Visitor must request for a lab coat from the laboratory officer before enter to the
laboratory.iii) No student is allowed to enter the laboratory unless permission has been given by
laboratory officer or lecturer.
II. At work in the laboratory:i) No experiment may be attempted without the knowledge and permission of lecturer
or lab officer.ii) Laboratory coat must be worn at all times in the laboratory.iii) Students must wear covered shoes in the laboratory. Students wearing open toes
shoes such as slippers or sandals are not allowed to work in the laboratory.iv) Safety glasses must be worn when necessary.v) Mobile phones are to be switched off at all times in the laboratory.vi) Do not smoke, drink, eat, bite nails or pencils, or apply cosmetics in the laboratory.vii) Do not pipette chemicals with mouth.viii) Do not taste any chemicals, including diluted solutions. If any acid or alkali
accidentally enters your eyes or mouth, wash immediately with plenty of water.Inform your lecturer or laboratory staff, and seek medical attention if necessary.
ix) Any accident must report to the lecturer or lab officer immediately.x) Paper should never be used to light up the Bunsen burners.xi) Used match sticks, filter papers, and other solid waste must never be thrown into the
sinks. They must be thrown into the dustbins provided. Lighted match sticks andsmoldering materials must be extinguished with tap water before thrown into thedustbins.
xii) Students must take responsibility for apparatus and equipment under their charge inthe laboratory.
xiii) Any glassware breakages, apparatus lost and equipment damages or malfunctioningmust be reported to the laboratory officer.
III. Before leaving the laboratory:i) Ensure all the equipments and working benches used are thoroughly cleaned and
dried.ii) Wash hands and arms with soap and water before leaving the laboratory.iii) All stools must be kept under the benches.iv) No student is allowed to take away any chemicals, equipment or other property of the
laboratory without permission.
Topic 1: Introductory to laboratory safety and apparatus________________________________________________________________________
1. Materials requirementThere are various materials that students must bring along during laboratory session.Students will be asked to leave the laboratory if they fail to bring the items listed. Laboratory manual Appropriate PPE (Personal Protective Equipment) Protective laboratory coating (Lab Coat) to protect you and your attire. Covered shoes to protect you from chemical burn or other hazards. Open toes
shoes are strictly not allowed. Safety glasses or goggles to protect your eyes.
Some other experimental materials which are requested by the lecturer. Calculator or scientific calculator. Record book to record observation and experiment results during lab sessions.
2. Practical ExercisesTo get the most out of the practical exercises, you are required to obey theinstructions given. These instructions have been designed to provide you withexperience in the following skills: Following instructions Handling apparatus Having due regards for safety Making accurate observations Recording results in an appropriate form Presenting quantitative results Gives valuable discussion Drawing conclusions
Following InstructionsFollow the sequence of instructions as they are provided in an appropriate order.Experimental procedures must be read through before carrying out the experiment. Drawout the procedure in a flow chart for better understanding of the steps for the experiment.
Apparatus HandlingBefore carrying out an experiment, it is important for scientists to plan and gather fortheir experiment apparatus. As such, you are advised to list down the apparatus to be usedfor the entire experiment before the start of the experiment. You will be able to masterthe basic technique of using different types of apparatus. These include measuringcylinder, bulb pipette, graduated glass pipette, volumetric flasks and burette. For differenttype of tasks, different set of the apparatus are to be used.
Laboratory Safety Always move slowly and carefully in the lab. During and after practical session, never touch your mouth or eyes with fingers before
thorough wash of hands with soap and water. Make sure glass objects (e.g: thermometer or glass rod) are not placed unattended on
the bench to prevent it from being rolled off from the working bench to the floor. Always put on your PPE such as lab coat, safety glasses and wear covered shoes in
the lab.Remarks: Proper heating using Bunsen burner (even with heating of water). Proper handling of any liquids, particularly those identified as corrosive, irritant, toxic
or harmful. Careful handling of corrosive work. Allow hot plate, Bunsen burner, tripods, gauzes and beakers to cool down before
handling them. Keep long hair tied and do not wear dangly earrings. Do not allow electrical equipment to come into contact with water. If you are not sure about how to carry out a scientific procedure, ask the lecturer or
lab officer. Make sure you understand the rationale and consequences of your actions before you
act. Follow all safety instructions given in the manual or provided by the lecturer/tutor for
particular experiments (e.g. use of gloves or mask).
Making Accurate ObservationThe experiment will make it clear about the needed observation, e.g. the color changeswhen two solutions are added together or time taken for a chemical reaction. Ensure thatyou know the proper handling of relevant equipment before the start of experiment.Think carefully about the precision of your observations. You may need to find outreference for color description from external sources (e.g. reference books or onlinereferences) before the practical session.
Recording Results in an Appropriate FormResults can be recorded in various ways. Often it is helpful to record raw data in a table.Most data will be in the form of numbers, e.g. quantitative data (also known as numericaldata). However, some data, e.g. color of solution, are qualitative. Bear in mind that thebest way for data collection is to avoid missing out any observation you have made, andkeep your raw data in safe hand.
Presenting Quantitative ResultsPresentation of data can be made using table, graph or other visual means to ease resultanalysis. You will have to choose the best way to present the experimental results.
Drawing ConclusionConclusions should be drawn from and supported by experimental results.3. Writing a Scientific Report
Title Refers to the subject investigated.Introduction State the hypotheses Give well-defined reason(s) for making hypotheses. Explain the chemical basis of the experiment. Cite sources to substantiate background information. Explain how the method used will produce information relevant to the
hypotheses. State a prediction based on the hypotheses.Material and Methods Use appropriate format. Give enough details (so that the experiment can be duplicated). State the control treatment, replication, and standardized variables that were used.Results Summarize the data (do not include raw data). Present the data in an appropriate format (table or graph). Present tables and figures neatly so they are easily read. Label the axes of each graph correctly. Give units of measurement where appropriate. Write a descriptive caption for each table and figure. Include a short paragraph pointing out the important results (do not interpret
the data). Do not create your own data which is not true.Discussion State whether the hypotheses was supported or proven false by the results, or else
state that the results were inconclusive. Cite specific results that support your conclusions. Compare the results, with your predictions and explain any unexpected results. Compare the results with other research or information available. Discuss any weaknesses the experimental design or problems with the
execution of the experiment. Discuss how you might extend or improve the experiment.Conclusion State conclusion which is supported by results Restate important results.Literature Cited Use proper citation form in the text.