This document provides instructions for calibrating common volumetric glassware used in analytical chemistry including volumetric flasks, pipettes, and burets. It explains that glassware must be calibrated to avoid systematic errors in measurements and outlines the general calibration procedure which involves weighing the amount of water contained or delivered, converting this to a volume using the density of water, and correcting to the standard temperature of 20°C. Tips for proper use of each type of glassware are also provided to reduce random errors.
Hello friends,
Abhilasha this side, i am going to update my new slide of glassware calibration . for any query you can drop me a mail.
Regards
Abhilasha Pandey
Analytical chemist
This document provides instructions for calibrating volumetric glassware used in a chemistry lab. Students will calibrate a 50 mL buret and volumetric pipet by weighing the amount of water delivered at a measured temperature. They will determine the "true volume" delivered and record the values to account for any errors in the glassware markings. Proper technique and care of glassware is emphasized to obtain precise quantitative measurements.
Calibration involves determining an instrument's accuracy by comparing its readings to a standard instrument. Instruments should be calibrated according to the manufacturer's recommendations, after repairs or modifications, periodically, or whenever readings seem questionable. Common laboratory equipment calibrated include volumetric flasks, burettes, and pipettes. The calibration process for each involves taking multiple measurements of known volumes of water and performing calculations to determine accuracy. Class A equipment has tighter tolerances and higher accuracy than Class B. Tolerance is the acceptable range of variation in measurements.
The document discusses the calibration of volumetric glassware used in analytical chemistry laboratories. It explains that volumetric glassware like burettes, pipettes, and volumetric flasks must be precisely calibrated to deliver accurate volumes of liquids. The document provides details on properly calibrating and using common types of volumetric glassware like burettes, pipettes, and volumetric flasks to ensure precise volume measurements.
This document describes two methods for determining the alcoholic content of gelanicals: distillation and chromatography. The distillation method involves diluting samples with water if over 50% alcohol by volume, then distilling and measuring the specific gravity or refractive index of the distillate to find the alcohol percentage using tables. Special treatments may be needed for volatile substances, glycerin, or iodine. Precautions like filtering distillates and avoiding foaming are also described.
Analytical balances have been used since 5000 BC, with the modern version originating in the mid-18th century developed by Joseph Black. There are several types of balances including analytical, micro, and top-load balances, which differ in capacity and sensitivity. Proper use and calibration of balances is important for accuracy and includes factors like location, temperature/humidity control, cleaning, and calibration schedules using certified weights.
Partition coefficient: To determine partition coefficient of benzoic acid bet...SONALI PAWAR
This document describes an experiment to determine the partition coefficient of benzoic acid between benzene and distilled water. The experiment involves preparing mixtures of benzoic acid saturated benzene solution and water in separating funnels, allowing the benzoic acid to distribute between the solvents, then measuring the concentrations in each solvent layer by titration. The partition coefficient is the ratio of concentrations of solute in the two solvents at equilibrium and this experiment aims to calculate it for benzoic acid between benzene and water.
Hello friends,
Abhilasha this side, i am going to update my new slide of glassware calibration . for any query you can drop me a mail.
Regards
Abhilasha Pandey
Analytical chemist
This document provides instructions for calibrating volumetric glassware used in a chemistry lab. Students will calibrate a 50 mL buret and volumetric pipet by weighing the amount of water delivered at a measured temperature. They will determine the "true volume" delivered and record the values to account for any errors in the glassware markings. Proper technique and care of glassware is emphasized to obtain precise quantitative measurements.
Calibration involves determining an instrument's accuracy by comparing its readings to a standard instrument. Instruments should be calibrated according to the manufacturer's recommendations, after repairs or modifications, periodically, or whenever readings seem questionable. Common laboratory equipment calibrated include volumetric flasks, burettes, and pipettes. The calibration process for each involves taking multiple measurements of known volumes of water and performing calculations to determine accuracy. Class A equipment has tighter tolerances and higher accuracy than Class B. Tolerance is the acceptable range of variation in measurements.
The document discusses the calibration of volumetric glassware used in analytical chemistry laboratories. It explains that volumetric glassware like burettes, pipettes, and volumetric flasks must be precisely calibrated to deliver accurate volumes of liquids. The document provides details on properly calibrating and using common types of volumetric glassware like burettes, pipettes, and volumetric flasks to ensure precise volume measurements.
This document describes two methods for determining the alcoholic content of gelanicals: distillation and chromatography. The distillation method involves diluting samples with water if over 50% alcohol by volume, then distilling and measuring the specific gravity or refractive index of the distillate to find the alcohol percentage using tables. Special treatments may be needed for volatile substances, glycerin, or iodine. Precautions like filtering distillates and avoiding foaming are also described.
Analytical balances have been used since 5000 BC, with the modern version originating in the mid-18th century developed by Joseph Black. There are several types of balances including analytical, micro, and top-load balances, which differ in capacity and sensitivity. Proper use and calibration of balances is important for accuracy and includes factors like location, temperature/humidity control, cleaning, and calibration schedules using certified weights.
Partition coefficient: To determine partition coefficient of benzoic acid bet...SONALI PAWAR
This document describes an experiment to determine the partition coefficient of benzoic acid between benzene and distilled water. The experiment involves preparing mixtures of benzoic acid saturated benzene solution and water in separating funnels, allowing the benzoic acid to distribute between the solvents, then measuring the concentrations in each solvent layer by titration. The partition coefficient is the ratio of concentrations of solute in the two solvents at equilibrium and this experiment aims to calculate it for benzoic acid between benzene and water.
Volumetric analysis involves determining the concentration of a substance by measuring the volume occupied. It is commonly used to determine the unknown concentration of a known reactant through a titration process, where one solution of known concentration and volume is used to react with another substance of unknown concentration until the reaction is complete. The volume of the known solution used is then used to calculate the concentration of the unknown substance. Accuracy in volumetric analysis relies on the use of standardized solutions of primary standards with known concentrations.
Distillation is a process that separates mixtures into their component parts based on differences in their boiling points. It involves vaporizing a liquid mixture and condensing the vapor to obtain purified fractions. There are several types of distillation processes that can be used for applications like purification of organic solvents, separation of drugs and petroleum products, and recovery of volatile oils and solvents. Some key distillation techniques described in the document include simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, and molecular distillation.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize components with lower boiling points and then condensing the vapors. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to lower boiling points of heat-sensitive materials. Distillation is an important separation technique used in pharmacy, chemistry, and other fields.
Everyone requires a product of the best quality, be it in case of medicines or any other edibles or services. Hence, the presentation deals with the quality control of tablets
Viscosity is a measure of a liquid's resistance to flow. It is defined as the shear stress divided by the rate of shear strain. There are several methods to measure viscosity, including using capillary tubes, rotating viscometers, and falling ball viscometers. The measurement involves determining the time required for liquid to flow through a capillary or for a ball to fall between marks in a viscometer tube, from which the dynamic viscosity in mPa·s can be calculated. Viscosity measurements require controlling the temperature accurately, usually within 0.1°C.
The document describes the Abbe refractometer, which is used to measure the refractive index of liquid samples. It has a prism lens made of two cemented prisms that allow a thin sample to be placed between them. A telescope is used to view the sharp boundary between the light and dark areas, and the refractive index is read from a scale by rotating the prism lens until this boundary is aligned with crosshairs in the eyepiece. The refractometer can determine how refractive index varies with temperature and wavelength of light by using different samples and a temperature controller and monochromatic light source.
Centrifugation is a process that uses centrifugal force to separate particles in suspension based on density differences. It works by spinning the suspension at high speeds, causing heavier particles to settle faster than lighter ones. There are several types of centrifuges that can be used including filtration, sedimentation, and continuous centrifuges. Filtration centrifuges separate particles through a perforated basket, sedimentation centrifuges separate in a solid walled vessel, and continuous centrifuges allow for high throughput separation. Key factors that affect centrifugation include liquid properties, particle characteristics, operating parameters, and centrifuge design features.
In this slide contains Determination of Acid value, Saponification value and Ester value.
Presented by: P.NARESH (Department of pharmaceutical analysis).RIPER, anantapur
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize more volatile components, which are then condensed and collected. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to reduce boiling points of heat-sensitive materials. Distillation is used in pharmacy and chemistry to extract and purify substances.
presented to : Dr | Hamdy El-Kady
Physical Chemistry Course 2016-2017
prepared By : Muhammad Mamdouh Abdulsalam
Faculty Of Petroleum Engineering, Suez University
This document summarizes an experiment to calibrate a pH meter and measure the pH of hair conditioners. The pH meter was calibrated using pH 4, 7, and 10 buffer solutions. The pH and electrode potential of three hair conditioner brands dissolved in water were then measured. The measured pH values were close to the calculated pH values based on electrode potential, with less than 1.3% error. The calibration process and measurements of hair conditioner pH provided an example of using a pH meter for analysis and quality control in various industries.
This document provides an overview of chromatography techniques. It discusses the definition and history of chromatography, and describes several types including paper chromatography, thin layer chromatography, column chromatography, gas chromatography, and high performance liquid chromatography. Specific details are provided on the principles, procedures, applications, advantages and disadvantages of paper chromatography and thin layer chromatography. Key differences between these two techniques are also compared.
This document discusses various techniques for purifying solid and liquid organic compounds. The common methods for purifying solids include crystallization, recrystallization, sublimation, and use of drying agents. Liquid organic compounds can be purified through distillation techniques like simple distillation, fractional distillation, and vacuum distillation. Other techniques mentioned are extraction, chromatography, and checking criteria like melting point and boiling point to confirm purity.
Analytical balances are highly sensitive weighing devices used to measure small masses in the sub-milligram range. They have an enclosed weighing pan inside a transparent draft shield to prevent dust and air currents from affecting measurements. Analytical balances must be calibrated regularly and located in areas free of vibration and electromagnetic interference to provide accurate readings. Proper weighing technique requires taring the balance, centering samples on the pan, and allowing readings to stabilize before recording results.
Rotational Viscometers,
The viscometers that used to measure the viscosity using retarding force due to the viscous drag.
typers and sub-types, advantages,disadvantages,working of different rotational viscometers.
1.cup and bob viscometer,
2.cone and plate viscometer,
plug flow development, etc.
Chapter: Rheology
4th semester B.Pharm.
Physical Pharmacuetics,
B.pharm, As per the PCI semester syllabus,
!THIS SLIDE IS SIMPLIFIED BULLETINS, USE THIS SLIDE AND REFER MORE RESPECTIVE TEXTBOOKS!.
THANK YOU:
This document discusses surface and interfacial phenomena. It defines interfaces and divides them into solid and liquid interfaces. Liquid interfaces deal with liquid-gas or liquid-liquid phases and have applications in infiltration, biopharmaceuticals, and suspensions/emulsions. Surface tension exists between solid-gas and liquid-gas phases, while interfacial tension exists between immiscible liquids. Various methods are described to measure surface tension, interfacial tension, and surface free energy. Surfactants are also discussed, including how they lower tensions and are used in products. Adsorption at interfaces and isotherms are briefly covered.
The document discusses the angle of repose, which is the maximum slope angle of non-cohesive granular materials before they collapse. It can be measured using methods like the tilting box method, fixed funnel method, and revolving cylinder method. Factors like particle size, moisture content, and measurement method can affect the measured angle of repose. Knowing the angle of repose is important for safely transporting and storing bulk materials.
A polarimeter is an instrument used to measure the angle of rotation caused when polarized light passes through an optically active substance. It consists of a polarimeter tube and operation panel. When light passes through a left-handed or right-handed sample, the translucent semicircular fields in the polarimeter gradually change. There are different types of polarimeters. The specific rotation, a unique property of substances, can be calculated using the measured angle of rotation, concentration, temperature, and length of the sample cell. Polarimeters are used in industries like chemistry, food, beverages, and pharmaceuticals for applications such as quality control and purity measurements.
This document discusses in-process quality control tests for liquid dosage forms, including sterile and non-sterile formulations. For sterile dosage forms like parenterals and ophthalmics, it describes tests for drug content, clarity, pyrogens, sterility, stability, leakage, and dye penetration. For non-sterile syrups and suspensions, it outlines testing drug content, active ingredient assays, pH, weight per ml, and particle size. The document provides details on procedures for each test and references for further information.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
Calibration establishes the relationship between instrument measurements and known standard values through a series of steps. Key aspects of calibration include identifying instruments and sources, following calibration procedures, documenting results, accounting for sources of error, and ensuring traceability to national standards. Calibration procedures vary based on instrument type, but generally involve evaluating instrument performance, establishing calibration curves using certified reference materials at multiple concentration levels, and quantifying samples based on the calibration curves.
Volumetric analysis involves determining the concentration of a substance by measuring the volume occupied. It is commonly used to determine the unknown concentration of a known reactant through a titration process, where one solution of known concentration and volume is used to react with another substance of unknown concentration until the reaction is complete. The volume of the known solution used is then used to calculate the concentration of the unknown substance. Accuracy in volumetric analysis relies on the use of standardized solutions of primary standards with known concentrations.
Distillation is a process that separates mixtures into their component parts based on differences in their boiling points. It involves vaporizing a liquid mixture and condensing the vapor to obtain purified fractions. There are several types of distillation processes that can be used for applications like purification of organic solvents, separation of drugs and petroleum products, and recovery of volatile oils and solvents. Some key distillation techniques described in the document include simple distillation, fractional distillation, distillation under reduced pressure, steam distillation, and molecular distillation.
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize components with lower boiling points and then condensing the vapors. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to lower boiling points of heat-sensitive materials. Distillation is an important separation technique used in pharmacy, chemistry, and other fields.
Everyone requires a product of the best quality, be it in case of medicines or any other edibles or services. Hence, the presentation deals with the quality control of tablets
Viscosity is a measure of a liquid's resistance to flow. It is defined as the shear stress divided by the rate of shear strain. There are several methods to measure viscosity, including using capillary tubes, rotating viscometers, and falling ball viscometers. The measurement involves determining the time required for liquid to flow through a capillary or for a ball to fall between marks in a viscometer tube, from which the dynamic viscosity in mPa·s can be calculated. Viscosity measurements require controlling the temperature accurately, usually within 0.1°C.
The document describes the Abbe refractometer, which is used to measure the refractive index of liquid samples. It has a prism lens made of two cemented prisms that allow a thin sample to be placed between them. A telescope is used to view the sharp boundary between the light and dark areas, and the refractive index is read from a scale by rotating the prism lens until this boundary is aligned with crosshairs in the eyepiece. The refractometer can determine how refractive index varies with temperature and wavelength of light by using different samples and a temperature controller and monochromatic light source.
Centrifugation is a process that uses centrifugal force to separate particles in suspension based on density differences. It works by spinning the suspension at high speeds, causing heavier particles to settle faster than lighter ones. There are several types of centrifuges that can be used including filtration, sedimentation, and continuous centrifuges. Filtration centrifuges separate particles through a perforated basket, sedimentation centrifuges separate in a solid walled vessel, and continuous centrifuges allow for high throughput separation. Key factors that affect centrifugation include liquid properties, particle characteristics, operating parameters, and centrifuge design features.
In this slide contains Determination of Acid value, Saponification value and Ester value.
Presented by: P.NARESH (Department of pharmaceutical analysis).RIPER, anantapur
Distillation is a method of separating mixtures based on differences in volatility. It involves heating a mixture to vaporize more volatile components, which are then condensed and collected. There are several types of distillation including simple distillation, fractional distillation, steam distillation, and destructive distillation. Fractional distillation uses a fractionating column with multiple theoretical plates to achieve high purity separations, while steam distillation uses steam to reduce boiling points of heat-sensitive materials. Distillation is used in pharmacy and chemistry to extract and purify substances.
presented to : Dr | Hamdy El-Kady
Physical Chemistry Course 2016-2017
prepared By : Muhammad Mamdouh Abdulsalam
Faculty Of Petroleum Engineering, Suez University
This document summarizes an experiment to calibrate a pH meter and measure the pH of hair conditioners. The pH meter was calibrated using pH 4, 7, and 10 buffer solutions. The pH and electrode potential of three hair conditioner brands dissolved in water were then measured. The measured pH values were close to the calculated pH values based on electrode potential, with less than 1.3% error. The calibration process and measurements of hair conditioner pH provided an example of using a pH meter for analysis and quality control in various industries.
This document provides an overview of chromatography techniques. It discusses the definition and history of chromatography, and describes several types including paper chromatography, thin layer chromatography, column chromatography, gas chromatography, and high performance liquid chromatography. Specific details are provided on the principles, procedures, applications, advantages and disadvantages of paper chromatography and thin layer chromatography. Key differences between these two techniques are also compared.
This document discusses various techniques for purifying solid and liquid organic compounds. The common methods for purifying solids include crystallization, recrystallization, sublimation, and use of drying agents. Liquid organic compounds can be purified through distillation techniques like simple distillation, fractional distillation, and vacuum distillation. Other techniques mentioned are extraction, chromatography, and checking criteria like melting point and boiling point to confirm purity.
Analytical balances are highly sensitive weighing devices used to measure small masses in the sub-milligram range. They have an enclosed weighing pan inside a transparent draft shield to prevent dust and air currents from affecting measurements. Analytical balances must be calibrated regularly and located in areas free of vibration and electromagnetic interference to provide accurate readings. Proper weighing technique requires taring the balance, centering samples on the pan, and allowing readings to stabilize before recording results.
Rotational Viscometers,
The viscometers that used to measure the viscosity using retarding force due to the viscous drag.
typers and sub-types, advantages,disadvantages,working of different rotational viscometers.
1.cup and bob viscometer,
2.cone and plate viscometer,
plug flow development, etc.
Chapter: Rheology
4th semester B.Pharm.
Physical Pharmacuetics,
B.pharm, As per the PCI semester syllabus,
!THIS SLIDE IS SIMPLIFIED BULLETINS, USE THIS SLIDE AND REFER MORE RESPECTIVE TEXTBOOKS!.
THANK YOU:
This document discusses surface and interfacial phenomena. It defines interfaces and divides them into solid and liquid interfaces. Liquid interfaces deal with liquid-gas or liquid-liquid phases and have applications in infiltration, biopharmaceuticals, and suspensions/emulsions. Surface tension exists between solid-gas and liquid-gas phases, while interfacial tension exists between immiscible liquids. Various methods are described to measure surface tension, interfacial tension, and surface free energy. Surfactants are also discussed, including how they lower tensions and are used in products. Adsorption at interfaces and isotherms are briefly covered.
The document discusses the angle of repose, which is the maximum slope angle of non-cohesive granular materials before they collapse. It can be measured using methods like the tilting box method, fixed funnel method, and revolving cylinder method. Factors like particle size, moisture content, and measurement method can affect the measured angle of repose. Knowing the angle of repose is important for safely transporting and storing bulk materials.
A polarimeter is an instrument used to measure the angle of rotation caused when polarized light passes through an optically active substance. It consists of a polarimeter tube and operation panel. When light passes through a left-handed or right-handed sample, the translucent semicircular fields in the polarimeter gradually change. There are different types of polarimeters. The specific rotation, a unique property of substances, can be calculated using the measured angle of rotation, concentration, temperature, and length of the sample cell. Polarimeters are used in industries like chemistry, food, beverages, and pharmaceuticals for applications such as quality control and purity measurements.
This document discusses in-process quality control tests for liquid dosage forms, including sterile and non-sterile formulations. For sterile dosage forms like parenterals and ophthalmics, it describes tests for drug content, clarity, pyrogens, sterility, stability, leakage, and dye penetration. For non-sterile syrups and suspensions, it outlines testing drug content, active ingredient assays, pH, weight per ml, and particle size. The document provides details on procedures for each test and references for further information.
Distillation is a process that separates components of a liquid mixture based on differences in their volatilities in heating and cooling processes. It involves selectively boiling the more volatile components by heating the mixture and then condensing the vapor.
There are several types of distillation including simple distillation, fractional distillation, steam distillation and vacuum distillation. Simple distillation is used to separate components with large differences in volatility, while fractional distillation allows separation of mixtures with components of similar volatility by conducting multiple distillation steps. Distillation finds applications in purification of solvents, separation of essential oils, and production of alcoholic beverages and petroleum products among others. Key aspects of distillation systems include the still, condenser and
Calibration establishes the relationship between instrument measurements and known standard values through a series of steps. Key aspects of calibration include identifying instruments and sources, following calibration procedures, documenting results, accounting for sources of error, and ensuring traceability to national standards. Calibration procedures vary based on instrument type, but generally involve evaluating instrument performance, establishing calibration curves using certified reference materials at multiple concentration levels, and quantifying samples based on the calibration curves.
The document discusses measurement, calibration, and units of measurement. Some key points:
- Measurement is the first step to control and improvement. If you can't measure something, you can't understand or control it.
- The International System of Units (SI) defines seven base units including the meter, kilogram, second, ampere, kelvin, mole, and candela. Other units are derived from these base units.
- Calibration establishes the relationship between measurement instruments and reference standards under specific conditions. Regular calibration helps ensure accuracy and traceability to national standards.
- Factors like instrument specifications, use, environment, and measurement accuracy needed should be considered when determining calibration frequency.
We used various instruments to create a calibration curve showing the relationship between absorbance and molarity of a potassium permanganate solution. Stock and daughter solutions were created through serial dilutions and transferred to spectrophotometer cells to measure absorbance at 535nm. The resulting data was plotted on a graph, where increasing absorbance correlated with increasing molarity. Some points fell outside the linear regression, possibly due to imprecise measurements when using burettes for dilution. Removing outlier data improved the linearity of the calibration curve.
This document describes a laboratory experiment to determine the concentration of hydrogen peroxide in a commercial antiseptic solution through redox titration. Potassium permanganate is used as the titrant to oxidize hydrogen peroxide. By measuring the volume of permanganate needed to reach the endpoint of the reaction, the concentration of hydrogen peroxide can be calculated. The purpose is to verify if the 3% concentration listed on commercial products is accurate. The procedure involves titrating a sample of the hydrogen peroxide solution with a standard permanganate solution and recording the volumes used in multiple trials to calculate an average concentration.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
Types of pipettes and its applications
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 other .
Calibration and validation of analytical instrumentsSolairajan A
This document discusses the calibration and validation of various analytical instruments used in pharmaceutical analysis. It provides details on calibrating UV-Vis spectrophotometers, IR spectrophotometers, spectrofluorimeters, HPLC, and GC. Calibration ensures instrument readings are accurate against standards, while validation confirms the instrument is correctly installed and operating as intended. The document outlines tests and acceptance criteria for evaluating characteristics like wavelength accuracy, resolution, noise, baseline flatness, sensitivity, flow rate, and linearity during calibration and validation of different analytical instruments.
The document discusses the anatomy, functions, and tests related to evaluating the liver. It notes that the liver is the largest organ located in the upper right abdomen and contains hepatocytes as its main cells. The liver has important metabolic, excretory, hematological, storage, protective, and detoxification functions. Common tests to evaluate liver function include assessing serum enzymes like AST, ALT, ALP, GGT, and bilirubin levels. Tests can also examine the liver's metabolic capacity through galactose tolerance or its synthetic function using prothrombin time.
Liver function tests can detect, distinguish, and monitor various types of liver disease. Tests are grouped based on the liver's excretory, metabolic, detoxification, storage and synthetic functions. Enzyme tests like ALT and AST indicate hepatocyte damage, while elevated ALP and GGT suggest cholestasis. Protein tests such as albumin, PT and AFP evaluate synthetic function. Bilirubin, bile salts and dye excretion tests examine excretory function. Together these tests provide insight into liver health and disease categories.
The document discusses liver function tests (LFTs) and their use in evaluating liver diseases. It provides details on 3 key LFTs:
1. Bilirubin tests which are used to diagnose prehepatic (hemolytic), hepatic, and obstructive jaundice. Elevated conjugated bilirubin indicates obstructive jaundice while elevated unconjugated bilirubin indicates hepatic or hemolytic jaundice.
2. Liver enzymes like ALT, AST, ALP, and GGT which provide information on liver health and injury. Elevated ALT and AST indicate liver parenchymal damage while elevated ALP and GGT can indicate obstructive jaundice.
3
The document provides instructions for preparing solutions in a chemistry laboratory. It discusses weighing solids and measuring liquids accurately, using equipment like volumetric flasks, graduated cylinders, and balances. The key steps are to weigh the solute, add it to part of the solvent in a volumetric flask, dissolve the solute, then fill the flask to the mark and mix thoroughly to obtain a homogeneous solution of known concentration. Proper technique and significant figures are important for obtaining precise results.
1. Digital balances allow for precise mass measurements and are important for experiments requiring exact amounts of substances. They must be placed on a stable, flat surface and containers must be tared to remove their mass from calculations.
2. Beakers and Erlenmeyer flasks are used to hold liquids and solids. Beakers have a pour spout and are used for mixing and transferring chemicals. Flasks can hold reactions or liquid samples and catch filtrates.
3. Burettes held in clamps and stands allow for accurate liquid measurements and dispensing. They are filled and used with a beaker or flask underneath to deliver specific volumes of reagents.
This document provides an introduction and overview of the process of titration. It begins by defining key concepts related to titration including volumetric analysis, titration, titrant, titrate, titre, and concordant titres. It then describes the types of specialized volumetric glassware used in titration - volumetric flasks, pipettes, and burettes. The document provides detailed instructions on cleaning and preparing this glassware, including how to rinse, fill, and calibrate each piece of equipment. Finally, it outlines the step-by-step process for performing a titration, including setting up the equipment, adding the titrant and titrate solutions, and monitoring the reaction until the endpoint is reached.
This document provides an introduction to common glassware and equipment used in labs, including:
1. Glassware like volumetric flasks, pipettes, burettes, and graduated cylinders are used to accurately measure volumes of solutions. Clean glassware is essential for accurate work.
2. Volumetric flasks come in different sizes and are used to make solutions of a precise volume. Solutions are added until the meniscus is at the marked line.
3. Pipettes like Mohr pipettes are used to accurately measure small volumes of liquids. They are filled and emptied through a bulb system to control flow.
4. Burettes are used for titrations to deliver reactants in
Instruments that are used in lab, their uses and mechanismProtik Biswas
Condensers are used to cool hot vapors and condense them into liquids. They are commonly used in reflux and distillation processes. A condenser consists of an inner glass tube surrounded by an outer tube through which coolant flows.
Suction pumps use atmospheric pressure and valves to draw liquid up through the pump. They are often used to accelerate filtration processes.
Buchner funnels speed up solid/liquid separation using vacuum filtration. The liquid is drawn through a perforated plate, leaving the solid component on a filter paper. They are mainly used to dry crystals after recrystallization.
Biochemistry
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A standard solution is one with a known concentration, usually given in mol/dm3. To make a standard solution accurately, the correct mass of the substance must be carefully measured and fully transferred to a volumetric flask. The procedure involves calculating the moles and mass needed, weighing out the substance, dissolving and transferring it to the flask, and filling to the line with water while mixing to produce a homogeneous solution. The completed solution is labeled with its concentration and details for identification and traceability.
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This experiment is designed to give you an opportunity to collect anraju957290
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1. CHEM 311L
Quantitative Analysis Laboratory
Revision 2.3
Calibration of Volumetric Glassware
In this laboratory exercise, we will calibrate the three types of glassware typically used by an
analytical chemist; a volumetric flask, a volumetric pipet and a buret. Over the course of this
semester, we will use these tools extensively when performing Gravimetric and Titrimetric
Analyses. In order to avoid introducing Systematic Errors into our measurements, each of these
instruments must be properly calibrated. And, to reduce the Random Errors inherent when using
these instruments, their proper use must be thoroughly understood. The quality of the
measurements obtained from these tools depends heavily on the care taken in calibrating and in
using each instrument.
Volumetric Flask (http://en.wikipedia.org/wiki/File:Brand_volumetric_flask_100ml.jpg)
Pipettes (http://www.chem.yorku.ca/courses/chem1000/equipment/pipette.html)
Buret (http://en.wikipedia.org/wiki/File:Burette_vertical.svg)
In precise work it is never safe to assume that the volume delivered by or contained in any
volumetric instrument is exactly the amount indicated by the calibration mark. Instead,
recalibration is usually performed by weighing the amount of water delivered by or contained in
the volumetric apparatus. This mass is then converted to the desired volume using the tabulated
density of Water:
Volume = mass / density (Eq. 1)
2. P a g e | 2
All volumetric apparati should be either purchased with a Calibration Certificate or calibrated by
the analyst in this manner.
Systematic Errors Affecting Volumetric Measurements
The volume occupied by a given mass of liquid varies with temperature, as does the volume of
the device that holds the liquid. 20o
C has been chosen as the normal temperature for calibration
of much volumetric glassware.
Glass is a fortunate choice for volumetric ware as it has a relatively small coefficient of thermal
expansion; a glass vessel which holds 1.00000L at 15o
C holds 1.00025L at 25o
C. If desired, the
volume values (V) obtained at a temperature (t) can be corrected to 20o
C by use of:
V20 = V [1 + 0.000025 (20 - t)] (Eq. 2)
In most work, this correction is small enough it may be ignored.
However, the thermal expansion of the contained liquid is frequently of importance. Dilute
aqueous solutions have a coefficient of thermal expansion of about 0.025%/o
C. A liter of water
at 15o
C will occupy 1.002L at 25o
C. A correction for this expansion must frequently be applied
during calibration procedures.
Parallax is another source of error when using volumetric ware. A correction for this expansion
must frequently be applied during calibration procedures. Frequently, graduation marks encircle
the apparatus to aid in this.
(Quantitative Analysis, 4th
Ed. by Conway Pierce,
Edward L. Haenisch and Donald T. Sawyer; John Wiley
& Sons; 1948.)
Readings which are either too high or too low will result otherwise.
3. P a g e | 3
Tips for Correct Use of Volumetric Glassware
Pipets
The Pipet is used to transfer a volume of solution from one container to another. Most
Volumetric Pipets are calibrated To-Deliver (TD); with a certain amount of the liquid
remaining in the tip and as a film along the inner barrel after delivery of the liquid. The
liquid in the tip should not be blown-out. Pipets of the "blow-out" variety will usually
have a ground glass ring at the top. And, drainage rates from the pipet must be carefully
controlled so as to leave a uniform and reproducible film along the inner glass surface.
Measuring Pipets will be gradated in appropriate units.
Once the pipet is cleaned and ready to use, make sure the outside of the tip is dry. Then
rinse the pipet with the solution to be transferred. Insert the tip into the liquid to be used
and draw enough of the liquid into the pipet to fill a small portion of the bulb. Hold the
liquid in the bulb by placing your fore finger over the end of the stem.
(Quantitative Analysis, 4th
Ed. by Conway Pierce,
Edward L. Haenisch and Donald T. Sawyer; John Wiley
& Sons; 1948.)
Withdraw the pipet from the liquid and gently rotate it at an angle so as to wet all
portions of the bulb. Drain out and discard the rinsing liquid. Repeat this once more.
To fill the pipet, insert it vertically in the liquid, with the tip near the bottom of the
container. Apply suction to draw the liquid above the graduation mark. Quickly place a
fore finger over the end of the stem. Withdraw the pipet from the liquid and use a dry
paper to wipe off the stem. Now place the tip of the pipet against the container from
which the liquid has been withdrawn and drain the excess liquid such that the meniscus is
at the graduation mark.
Move the pipet to the receiving container and allow the liquid to flow out (avoiding
splashing) of the pipet freely. When most of the liquid has drained from the pipet, touch
the tip to the wall of the container until the flow stops and for an additional count of 10.
4. P a g e | 4
Volumetric Flasks
The Volumetric Flask is used to prepare Standard Solutions or in diluting a sample. Most
of these flasks are calibrated To-Contain (TC) a given volume of liquid. When using a
flask, the solution or solid to be diluted is added and solvent is added until the flask is
about two-thirds full. It is important to rinse down any solid or liquid which has adhered
to the neck. Swirl the solution until it is thoroughly mixed. Now add solvent until the
meniscus is at the calibration mark. If any droplets of solvent adhere to the neck, use a
piece of tissue to blot these out. Stopper the flask securely and invert the flask at least 10
times.
Burets
The Buret is used to accurately deliver a variable amount of liquid. Fill the buret to
above the zero mark and open the stopcock to fill the tip. Work air bubbles out of the tip
by rapidly squirting the liquid through the tip or tapping the tip while solution is draining.
The initial buret reading is taken a few seconds, ten to twenty, after the drainage of liquid
has ceased. The meniscus can be highlighted by holding a white piece of paper with a
heavy black mark on it behind the buret.
(Quantitative Analysis, 4th
Ed. by Conway Pierce,
Edward L. Haenisch and Donald T. Sawyer; John Wiley
& Sons; 1948.)
Place the flask into which the liquid is to be drained on a white piece of paper. (This is
done during a titration to help visualize color changes which occur during the titration.)
The flask is swirled with the right-hand while the stopcock is manipulated with the left-
hand.
(Quantitative Analysis, 4th
Ed. by Conway Pierce,
Edward L. Haenisch and Donald T. Sawyer; John Wiley
& Sons; 1948.)
5. P a g e | 5
The buret should be opened and allowed to drain freely until near the point where liquid
will no longer be added to the flask. Smaller additions are made as the end-point of the
addition is neared. Allow a few seconds after closing the stopcock before making any
readings. At the end-point, read the buret in a manner similar to that above.
As with pipets, drainage rates must be controlled so as to provide a reproducible liquid
film along the inner barrel of the buret.
Cleaning Volumetric Glassware
Cleaning of volumetric glassware is necessary to not only remove any contaminants, but to
ensure its accurate use. The film of water which adheres to the inner glass wall of a container as
it is emptied must be uniform.
Two or three rinsings with tap water, a moderate amount of agitation with a dilute detergent
solution, several rinsings with tap water, and two or three rinsings with distilled water are
generally sufficient if the glassware is emptied and cleaned immediately after use.
If needed, use a warm detergent solution (60-70o
C). A buret or test tube brush can be used in the
cleaning of burets and the neck of volumetric flasks. Volumetric flasks can be filled with
cleaning solution directly. Pipets and burets should be filled by inverting them and drawing the
cleaning solution into the device with suction. Avoid getting cleaning solution in the stopcock.
Allow the warm cleaning solution to stand in the device for about 15 minutes; never longer than
20 minutes. Drain the cleaning solution and rinse thoroughly with tap water and finally 2-3
times with distilled water.
Pipets and burets should be rinsed at least once with the solution with which they are to filled
before use.
A General Calibration Procedure
As was noted above, volumetric glassware is calibrated by measuring the mass of Water that is
Contained In or Delivered By the device.
To obtain an accurate mass measurement, buoyancy effects must be corrected for. The amount
of air displaced by the standard weights of the balance is somewhat different than the amount of
air displaced by the weighed water. This difference leads to different buoyancies for these
objects; meaning the balance levels at a point other than when the two objects are of the same
mass. This can be corrected for using:
mtrue = mmeas + da ( (mmeas/d) – (mmeas/ds) ) (Eq. 3)
6. P a g e | 6
where ds is the density of the standard weights (8.47 g/cm3
), da is the density of air ( 0.0012
g/cm3
), and d is the density of the object being measured.
This mass data is then converted to volume data using the tabulated density of Water (See
Appendix) at the temperature of calibration. (In very accurate work, the thermometer must also
be calibrated as an incorrect temperature reading will lead to the use of an incorrect density for
Water. This, in turn, will give an inaccurate volume calibration.)
Finally, this volume data is corrected to the standard temperature of 20o
C. This can be
accomplished using the thermal expansion coefficient of Water; 0.00025/o
C:
V20 = V [1 + 0.00025 (20 - t)] (Eq. 4)
Further details concerning calibration of laboratory glassware can be found in the NIST
publication “The Calibration of Small Volumetric Laboratory Glassware” by Josephine
Lembeck; NBSIR 74-461. This publication can be found at:
http://ts.nist.gov/MeasurementServices/Calibrations/upload/74-461.PDF
Thus, in this exercise we will calibrate a volumetric flask and a pipet and determine a buret
Correction Factor by calibrating each of these devices with Water. In each case, the measured
mass of the calibrating Water will be corrected for buoyancy effects and the resulting volume
will be standardized to 20o
C.
7. P a g e | 7
Procedures
Begin by cleaning a 5 mL or 25 mL Volumetric Pipet, a 50 mL Buret, and a 25 mL
Volumetric Flask according to the procedure outlined above. It is imperative for the
purposes of calibration that these glassware items be cleaned such that Water drains
uniformly and does not leave breaks or droplets on the walls of the glass.
If detergent solutions are not sufficient to clean your glassware, a Cleaning Solution
(Dichromate in Conc. Sulfuric Acid) may be used. Consult you instructor before taking
this step.
Once cleaned, the Buret should be filled with Distilled Water and clamped in an upright
position and stored in this manner until needed. The Volumetric Flask should be clamped
in an inverted position so that it may dry.
Calibration of a Pipet
Use your cleaned pipet. Note if this is a Class A or other device. Weigh a receiving container on
the Analytical Balance; a 100 mL plastic beaker with Aluminum Foil cover. Pipet distilled water
into the plastic beaker and reweigh it.
Record the temperature of the water used.
Repeat the procedure at least 2 more times. Dry the plastic beaker and re-weigh it for each
replication. (Are you pipeting consistently and correctly?)
Calculate the apparent mass and the buoyancy corrected mass of the water delivered for each
time you pipet. From this mass, and the density of water at the given temperature (See
Appendix), calculate the volume of the water delivered. Correct the volume to 20o
C. Calculate
the Average, Standard Deviation and 90% Confidence Interval for your calibration result.
Is your result within the listed tolerance for this pipet? (See Appendix. What is the better
question to ask?)
Calibration of a Buret
Use your cleaned 50mL buret. Note if this is a Class A or other device. Fill the buret with
water. Make sure the tip is free of bubbles. Drain into a waste beaker until it is at, or just below,
the zero mark. Allow 10-20 seconds for drainage. Make an initial reading to a precision of at
least 0.01 mL. Test for tightness of the stopcock by allowing the buret to stand for 5 minutes and
then re-reading the volume. There should be no noticeable change in the reading.
8. P a g e | 8
Once the tightness of the stopcock is assured, refill the buret and again drain into a waste until it
is at, or just below, the zero mark. Allow for drainage. Touch the tip of the buret to the wall of
the waste beaker to remove the pendent drop of water. Make a volume reading.
Weigh a receiving container on the Analytical Balance; a 100 mL plastic beaker with Aluminum
Foil cover. Drain about 5 mL of water from the buret into the beaker. Allow 10-20 seconds for
drainage. Touch the tip of the buret to the wall of the beaker to again remove the pendent drop.
Read the buret and weigh the water.
Calculate the actual volume of water delivered by the buret in the same manner as outlined above
in the procedure on calibrating pipets. Calculate the Correction Factor by subtracting the
apparent volume delivered, as given by the buret readings, from the actual volume delivered.
Repeat the procedure at least once more. The two Correction Factors should agree within 0.04
mL. If they do not, repeat the procedure again. Report the average Correction Factor for 5 mL.
Repeat this process for 15 mL, 25 mL, 35 mL, and 45 mL delivered.
Plot the Average Buret Correction Factor vs. Volume Delivered using Excel or some other
graphing software.
Label and store your buret properly; upright and filled with Distilled Water. This is the
buret you will use for the remainder of the course.
Calibration of a Volumetric Flask
Use your cleaned 25mL volumetric flask. Note if this is a Class A or other device. Weigh the
flask empty. Fill the flask to the mark and re-weigh it. Measure the temperature of the water
used.
Repeat the procedure at least twice more.
Calculate the true volume of the flask using the method outlined above. Report the Average,
Standard Deviation, and 90% Confidence Interval for this result.
Is your result within the listed tolerance for this flask?
9. P a g e | 9
Appendix - Density of Water
Temperature (o
C) Density (g/mL)
10 0.9997026
11 0.9996084
12 0.9995004
13 0.9993801
14 0.9992474
15 0.9991026
16 0.9989460
17 0.9987779
18 0.9985986
19 0.9984082
20 0.9982071
21 0.9979955
22 0.9977735
23 0.9975415
24 0.9972995
25 0.9970479
26 0.9967867
27 0.9965162
28 0.9962365
29 0.9959478
30 0.9956502
10. P a g e | 10
Appendix - Tolerances for Class A Volumetric Glassware at 20o
C
Pipets
Capacity (mL) Tolerances (mL)
0.5 0.006
1 0.006
2 0.006
5 0.01
10 0.02
20 0.03
25 0.03
50 0.05
100 0.08
Volumetric Flasks
Capacity (mL) Tolerances (mL)
5 0.02
10 0.02
25 0.03
50 0.05
100 0.08
250 0.12
500 0.20
1000 0.30
2000 0.50
Burets
Capacity (mL) Tolerances (mL)
5 0.01
10 0.02
25 0.03
50 0.05
100 0.20
With the exception of Graduated Cylinders, the Tolerances for Class B devices is
typically twice that of a Class A device. (ASTM E694)