Thank you for your patience as we work hard to communicate current order status and increase our service levels. EMAIL: customerservice riccachemical. Customer Support. Technical Support. About Us. Contact Us. Search for:. Collect the water from the pipette into a clean, dry previously weighed beaker [For burette — drain the water up to the lower mark]. Take the weight of beaker with water. Check the weight of water by subtracting the wt.
Capacity in ml. Class A. Subdivision in ml. Frequency: Initially when volumetric glassware is purchased. Note: When the volumetric glassware does not comply with the requirement as specified above, the volumetric glassware should be returned back to the party.
Calibration Of Glassware Accuracy is the most crucial factor in quantitative chemistry. Types of Glassware Laboratory glassware is made from borosilicate glassware which is resistant to thermal shock and chemical attack.
Two categories of glassware are commonly used in laboratories: Type A Type A glassware is used for work requiring highest accuracy of results. Type B Double the tolerance limit of class A glassware.
Cleaning of Glassware Labware Washing Machines Volumetric glassware must be washed and dried before use as unclean glassware can introduce contamination errors. Soak used glassware in water and drain. Clean with a cleaning detergent. Rinse with dilute potassium dichromate solution in sulphuric acid. New glassware is slightly alkaline in nature so soak in slightly acidic solution e. Suppliers of laboratory glassware washing machine include: Labconco Lancer Miele Cole Parmer Scientek Care in Handling of Volumetric Glassware When washing take special care so that it does not break on striking wash basin walls When shaking a volumetric flask, hold both neck and bottom using both hands to prevent breakage Remove the stopper from volumetric flask before oven drying.
Calibration of Glassware Calibration of volumetric apparatus at specified intervals is an important task. Volume, weight and delivery time at calibration temperature are common parameters for calibrations. Clean apparatus will offer more accurate outcomes. It can be calibrated conveniently.
The cross-contamination risk gets reduced. Well-maintained pipettes last longer. Calibration of Burette A burette is a narrow and long glass tube that comes with a stopcock at the base. Record the delivery time and volume for consistent results. Calibration of Volumetric Flask Unlike other glassware equipment on the list, a volumetric flask is used for mixing or preparing a certain amount of any solution.
Never lay or invert a loaded micropipette down or tilt it as this could allow liquid to run into the pipette barrel. Use the micropipette for only the specified pipetting range. Wipe droplets if any from the sides of tip but never wipe the tip opening. Never use a micropipette without a tip as it will contaminate the shaft assembly. Store micropipette set to its maximum volume.
This releases pressure in the spring inside the micropipette. If trying to pipette organic solvents make sure they are compatible with the tip and also allow solvents to come to room temperature before pipetting. Calibration of Micropipettes These are used for the same purpose as a regular pipette. To calibrate them, one can follow these simple steps: Label and weigh five centrifuge tubes. Using single tip to transfer same volume in each centrifuge tube with single low range volume.
Weigh each tube and record weight of water transferred into each tube. Repeat above steps with single upper range volume of micropipette. Choice of Balance for Micropipette Calibration Weighing of transferred volumes requires different types of balances for the required accuracies Micropipette capacity Balance to be used 0.
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