LAB 2 : INSTRUMENTATION

SBL 1023 - Lab 2

• INTRODUCTION

What is exactly mean by instrumentation? It is the art and science of measurement and control of process variables within a production, laboratory, or manufacturing area.

A device that measures a physical quantity such as flow, temperature, level, distance, angle, or pressure, we call it as instruments that we use in instrumentation. Instruments may be as simple as direct reading thermometers or may be complex multi-variable process analyzers. Instruments are often part of a control system in refineries, factories, and vehicles.

To be certain of accurate and reliable measurements, you need to perform pH meter calibration. This is generally done by measuring different buffer solutions with standardized, well-defined values, and then adjusting the pH meter based on any deviations from the buffer’s known pH value.

Micropipettes are utilized in the laboratory to transfer small quantities of liquid, usually down to 0.1 uL. They are most commonly used in chemistry, biology, forensic, pharmaceutical, and drug discovery labs, among others.

Not only do micropipettes differ in size and volume dispensed, but depending on those particular aspects they also require specific pipette tips. Micropipettes use a disposable pipette tip to aspirate liquid, note that the tip is the only part of the pipette that makes contact with the solution. A new tip is utilized for every sample in order to prevent cross contamination.

• Objective

1. To determine how to calibrate the pH meter with different pH of buffer solutions and measure the pH for solution x, y and z.
2. To determine how to use the micropipette.
3. To determine how to use the microscope and observe the specimen using 4x, 10x, 40x and 100x magnifications.

•  Method

A) Calibration of pH meter

1- The protective end cover was removed from the electrode.

2- The electrode was cleaned with distilled water and the excess water was wiped with tissue.

3- The Setup button on pH meter was pressed for a few times until the screen display the set of pH buffer that want to be calibrated (pH 4,7,10).

4- The Standardize button was pressed and students were waited for the signal on the screen and then the electrode was placed into the first buffer (pH 4) after the signal was appeared on the screen.

5- The meter was recognized the buffer and displayed the  first value. Then, the display was indicated either good electrode “OK” or electrode error “Error”.

6- After “OK” was displayed the electrode was taken out and was rinsed again with distilled water, and then the excess water was wiped with the tissue. Always make sure that the electrode was rinsed with distilled water between each measurement.

7- The Standardize button was pressed and students were waited for the signal on the screen and then the electrode was placed into the second buffer (pH 7) after the signal was appeared on the screen. The same procedure was repeated until all buffer have been standardized.

8- Once, the calibration was done, measure pH for solution labeled as x,y,z.

B) Micropipette

1. The desire volume was set by turning the centrally located rings clockwise to increase volume or counter clockwise to decrease volume.

2. A sterile tip was loaded. The proper size tip was used for each pipette. The tip box was closed to maintain sterility. The pipette tip was not allowed to touch any object.

3. The sample was loaded. The plunger will stop at two different positions when it depressed. The plunger was pushed down slowly to the point of first resistance : this was the load volume.

  4. The tip was put into the solution while the plunger was hold at the load volume set point so                 that it is immersed just enough to cover the end (3-4mm).

5. The plunger was slowly released to draw up the liquid and the tip was keep immersed.

6. The sample was delivered. The second stopping point can be found when the plunger is depressed beyond the initial resistance until it is in contact with the bosy of the pipette. This second stopping point was used for the complete discharging of solutions from the plastic tip. The second stop was not reached when drawing liquid into the pipettes, only when expelling the last drop.

7. The tip was placed into the receiving vessel. The plunger was depressed all the way to the bottom to expel all the liquid.

8. The discharge slider on the back of the grip was pressed to discharge the tip.

C) Microscope

1. A prepared slide was picked and observed under the microscope using different magnification.

2. The low power (4x) on the microscope was used to locate the specimen on the prepares slide. The observation was draw on the paper.

3. The power was carefully switched to high power after student have centered the specimen that was viewed in the center of the field of view. The observation was draw on the paper.

4. The procedure was repeated using the higher magnifications up to 100x magnification.

5. The observation under the microscope using 4x, 10x, 40x, and 100x magnifications was draw.

• RESULT

1. Calibration of pH meter

a) pH 4

b) pH 7

c) pH 10

i) pH x

ii) pH y

iii) pH z

2. Micropipette

3. Microscope

i) 4x

ii) 10x

iii) 40x

iv) 100x

• Discussion

1. Calibration of pH meter

 In your opinion, why it is necessary for all buffer solution to be at the same temperature during calibration?

A buffer pH solution is composed of either a weak acid and the conjugated base or a weak base and the conjugated acid.  The main characteristic of a buffer pH calibration solution is that the pH value of the solution will not alter when a small amount of acid or a base is added [1].  The components and their concentration can cause the pH value of the calibration solution to vary across a large range e.g. with HCl and sodium citrate (pH 1-5), citric acid and sodium citrate (2.5 - 5.6), acetic acid and sodium acetate (3.7-5.6), Na₂HPO₄ and NaH₂HPO₄ (6-9) or borax sodium hydroxide (9.2-11).

The pH value of a calibration solution does not only alter with its composition but with temperature changes.  An exact specification of reference pH calibration solutions is given by the DIN 19266 [2].  The thermal characteristics of these buffer pH calibration solutions have been determined by metrological institutes . In contrast to reference pH calibration solutions the composition of technical buffer pH solutions is not regulated.  So it is important to note that the temperature reaction of those pH calibration solutions can vary, even if the same nominal pH value is specified at 25°C.  In particular at a calibration temperature other than 25°C considerable errors can occur with the pH measurementresults.  In addition to different kinds of buffer pH solutions the calibration procedure plays a major role in determining the accuracy of the pH measurement.

2. Micropipette

i. Why it is encourage to always select the SMALLEST size pipette that will handle the volume you wish to move?

Always select the SMALLEST size pipet that will handle the volume you wish to move to achieve the greatest accuracy. Accuracy decreases as you use unnecessarily large pipets for small volumes.

ii. Why the liquids from the pipette need to be release slowly, especially with large volume pipettes?

To exceed these values will put the pipet out of calibration.

iii. Why the pipette cannot be point up?

We will get air bubbles when collecting the liquid

3. Microscope

Draw what you observed under the microscope using 4x, 10x, 40x and 100x magnifications.

• 10x

• 40x

• 100x

• Conclusion

Based on the experiment conducted, we can conclude that the pH meter was standardized with buffer solutions of pH = 4, pH = 7 and pH = 10. The pH of different solutions were measured with the meter. Next, the micropipette was used to measure the small volumes of liquids. Last but not least, for the microscope, we can conclude that 10x objective 10x eyepiece = 100x magnification able to give clear and almost detail within the images of specimen being observed.

• Reference

Osuna, C. (2017, July 25). What is a micropipette? Retrieved from

https://solutions.pipette.com/micropipette/

       What is a pH Meter and Why is pH Meter Calibration Important? (2018, March 30). Retrieved from https://www.rscal.com/what-is-a-ph-meter-and-why-is-ph-meter-calibration-important/

SBL 1023 - LABORATORY REPORT OF EXPERIMENT 1

EXPERIMENT 1 : LABORATORY SAFETY

• Introduction

  In some laboratories, the conditions are no more dangerous than in any other room. Lab environments expose workers to numerous hazards including chemical, biological, physical and radioactive hazards. In laboratories where the dangerous conditions might exist, safety precautions are important. Rules exist to minimize the individual’s risk, and safety equipment is used to protect the lab user from injury or to assist in responding to an emergency. Lab equipment and chemicals that are improperly handled can result in personal injury and even death. Chemical spills, toxic fumes, needle pricks, and fires can harm lab workers and all the people either in or surrounding of the laboratory.

In this experiment, we will learn more detail about the safety rules in laboratory. Laboratory safety is including :

1) Laboratory safety procedure

2) Protective procedure

3) Emergency procedure

4) Chemical safety

•  Objective

i. To make sure that all of the students are ready mentally and physically before enter the lab.

ii. To give students more knowledge and information about lab safety procedures.

iii. To make sure safety are priority until the end of the experiments.

• Method

Laboratory safety procedures: 

a) Reporting all spills and broken glassware to the instructor and receiving instructions for clean up.

b) Washing hands prior to and following laboratories and at anytime contamination is suspected.

c) Disinfecting lab benches and equipment prior to and at the conclusion of each lab session, using an appropriate disinfectant, and allowing a suitable contact time.

d) Identification and proper disposal of different types of waste.

e) Reading and signing a laboratory safety arrangement indicating that the student has read and understands the safety rules of the laboratory.

f) Good lab practice, including returning materials to proper locations, proper care and handling of equipment, and keeping the bench top clear of extraneous materials. 

Protective procedures:

a) Wearing long pants or dresses (NO shorts, NO sandals).

b) Tying long hair back, wearing personal protective equipment (eye protection, coats, gloves; glasses may be preferred to contact lenses), and using such equipment in appropriate situations.

c) Always using appropriate pipetting devices and understanding that mouth pipetting is forbidden.

d) Never eating or drinking in the laboratory.

Emergency procedures:

a) Locating and properly using emergency equipment (eye wash stations, first aid kits, fire extinguishers, chemical safety showers, telephones and emergency numbers).

b) Reporting all injuries immediately to the instructor.

c) Following proper steps in the event of an emergency.

Chemical safety:

a) Treat every chemical as if it were hazardous.

b) Never "smell" a solvent!! Read the label on the solvent bottle to identify its contents.

c) Make sure all chemicals are clearly and currently labeled with the substance name, concentration, date, and name of the individual responsible.

d) Never return chemicals to reagent bottles. (Try for the correct amount and share any excess).

e) Close chemical bottle immediately after use.

f) Comply with fire regulations concerning storage quantities, types of approved containers and cabinets, proper labeling, etc. If uncertain about regulations, contact the building coordinator.

g) Use volatile and flammable compounds only in a fume hood. Procedures that produce aerosols should be performed in a hood to prevent inhalation of hazardous material.

h) Never allow a solvent to come in contact with your skin. Always use gloves.

i) Dispose of waste and broken glassware in proper containers.

j) Clean up spills immediately

• Result

ACTIVITY 1

List the Protective Procedure in your lab. Attach pictures as proof.

List of protective procedure in lab	What error (if any) did you observed?
Wear glove when handling any chemicals.
Wear gloves, eye protection and other protective equipment in appropriate situations.
Always wear a suitable attire when entering the lab.
When entering the lab, we must always wear a suitable footwear.
Any food and drink are prohibited.
Dispose any types of waste according to the label.

ACTIVITY 2

Locate and list the Emergency Procedure in your lab. Attach pictures as proof.

List of emergency procedure in lab	What error (if any) did you observed?
Chemical safety shower and eye wash station. (the front area of the lab)	The chemical safety shower is not functioning due shower valve was broken.
Fire extinguisher (nearby the door)
Plan location in any case of emergency. (Under the main switch)
Exit sign above each doors in the lab.
Emergency number that can be contact. (attach on the window)
First aid kit ( at the back area of the lab)
Fire blanket (at the back area of the lab)

ACTIVITY 3

Identify the hazardous level of 5 laboratory chemicals in your lab. Attach pictures as proof.

Laboratory chemicals	Hazardous level (NFPA Label, Pictogram)
Ethyl Alcohol
Sulphuric acid
Potassium permanganate
Sodium Hydroxide
Acetic acid

• Discussion

What we have learnt in this laboratory safety is, we have to be more careful especially with the physical,biological and chemical hazards. We also need to know about laboratory safety procedures , protective procedures,emergency procedures and also chemical safety.

When we are in lab, we have to wear some laboratory safety,which is wear glove, wear foot protection , wear lab coat, wear goggles and also face mask.

Lab safety

1. Protective Procedure In lab list.

List of protective procedure in lab	The error (if any) that we observed
a) Wear glove b) Wear foot protection c) Lab coats must be worn d) No food and no drink allowed e) No smoking f) Wear goggles g) Face mask	-

2. Emergency Procedure in lab locate and list.

List of emergency procedure in lab	The error (if any) that we observed
a) Safety first b) First aid and fire blanket c) Fire extinguisher d) Eyewash e) Emergency calls	a) Eyewash

•    Conclusion

From the Experiment 1, students gain more knowledge about the safety rules that must be followed by all the students. There are 4 main protections such as laboratory safety procedures, protective procedures, emergency procedures and chemical safety. All of this protections are very important and student should be able to understand and obey all the rules to make sure their safety are always the priority.

For laboratory safety procedures, students learned about responsibility and action that must be taken when something bad happen in laboratory. We also learned about cleanliness to protect our body from any hazards that can be harmful for people.

Then, for protective procedures, students learned about all the rules before entering the laboratory. For example, student should wear gloves, goggles, lab coat and so on. Therefore, student also learned about the rules when the experiment is in progress. For example, students are advised to always using the appropriate tools for each experiment and never eating or drinking in the laboratory during the experiment.

In the same time, for emergency procedures, students learned about the proper steps that must have follow in the event of an emergency such as the location of emergency equipment  and their function. We also need to know the emergency number and the instructor for each laboratory.

    Lastly, for chemical safety, student learned about the functions, hazards and label on each chemical in laboratory and its prevention. Students also learned about how to use chemical the right way and the procedures that students should follow to be safe in laboratory.

  

• Reference

Anne Marie Helmenstine. (June 26,2018). The 10 Most Important Lb Safety Rules. Retrieved from https://www.thoughtco.com/important-lab-safety-rules-608156

           George H, Wahl, Jr and Maria T.Gallardo-Williams. (2011). Laboratory Safety Rules and Regulations. Retrieved from http://www.webassign.net/sample/ncsumeorgchem2/safety/manual.html 

          Lab Manager. (December 7, 2017). Lab Safety Rules and Guideline. Retrieved from https://www.labmanager.com/lab-health-and-safety/2017/12/science-laboratory-safety-rules-guidelines#.W_qnjDgzaM8

         Stony Brook. (2008). Lab Safety Guide. New York. Retrieved from  https://ehs.stonybrook.edu/programs/laboratory-safety/lab-safety-guide