What are three major safety rules you should follow when working with open flames?

What are three major safety rules you should follow when working with open flames?

Personal Safety Participants with long hair should secure it away from the face so it doesn’t fall down into the flame. Remove any long jewelry that might reach the flame. Safety gear is also key. Wear goggles when using the flame, especially if you’re heating a glass container or using chemicals.

Which is one precaution to take when working with heat and fire do not use during experiments Keep flammables away Avoid touching face and eyes do not mix chemicals unless told to do so?

Answer: 1) Turn off heat sources when they are not in use. 2) Point test tubes away from yourself and others when heating substances in them. 3) Use the proper procedures when lighting a Bunsen burner.

Why should you never Heat heavy walled glassware directly with a flame?

Pyrex glassware is usually safe to heat but never apply the direct heat of a flame to heavy glassware such as volumetric flasks, burettes, graduated cylinders, bottles, and thermometers. Volumetric glassware will be permanently distorted from the calibrated volumes.

What property is important for glasswares that are heated?

When glass is heated to a temperature below the lower annealing point, the thermal expansion and the poor thermal conductivity result in tensile and compressive stresses within the glass surface.

What is the simple rule of handling glassware?

When carrying glassware, be sure to: Use both hands; Never hold it by its neck; Never carry it by its side.

What should you do to all glassware before using it?

All glassware should be inspected for cracks and contamination before use. Cracked items should be disposed of, and contaminated glassware should be cleaned. Broken and other waste glass should be discarded in a container specially marked to indicate its contents.

What are the different types of glassware?

There are four main types or strengths of glass:

• Annealed Glass. Annealed glass is a basic product formed from the annealing stage of the float process.
• Heat Strengthened Glass. Heat Strengthened Glass is semi tempered or semi toughened glass.
• Tempered or Toughened Glass.
• Laminated Glass.

How do you handle glasswares properly give at least five tips?

Never carry a flask by its neck. Never carry a beaker by its side. Always use two hands carrying any glassware (position one hand under the glass for support)….Handle and Store Glassware Safely

1. Never force a joint free.
2. Lubricate surfaces or use a Teflon sleeve.
3. A heat gun can gently loosen the joints.

What should you not put on glass?

Try not put hot items in cold glass. If you have just rinsed your glass in cold water or it has been in a cold location, pouring hot tea, coffee or placing other heated items into it can cause it to stress and crack.

What is the proper way of handling flatware and glassware?

When setting up flatware and glasses, avoid leaving finger marks; carry them in trays or with a cloth napkin. Never serve food using cutleries that have fallen on the floor. To avoid contamination, food must be covered when it is not served immediately.

Why is immediate rinsing of glasswares important?

Keeping the laboratory glassware physically neat and clean, free of grease, and bacteria is therefore of the utmost importance. To keep your glass labware neat and clean, you must wash it immediately after use. Chromic acid solution is quite effective in cleaning unduly clouded or dirty glassware.

What are three examples of surfaces that need to be cleaned?

Cleaning of surfaces (windows, buildings, automobiles) and wearables (fabrics) are resource intensive and a major strain on our water resources [104].

How do you maintain a burette?

To clean the buret, use the following procedure:

1. Rinse with distilled water. With the stopcock closed, add some distilled water to the buret.
2. Rinse with solution.
3. After you are finished with the buret in your experiment, rinse it by filling it with distilled water and allowing it to drain.

Why is it important to condition a pipette?

It means to pipet (or inspirate, suck up) some of the liquid that you are going to measure with the pipet to coat the inside of the glass and let it drain out, before you actually measure the amount that you want.

What is the purpose of using burette?

A burette is used to dispense small volumes of liquid called aliquots, or sometimes gas, with high accuracy. It consists of a long glass tube with a valve at one end to control the flow of liquid. Burettes serve essentially the same purpose as a pipette.

Why is it important to condition a Buret?

Using a Buret To condition a piece of glassware, rinse it so that all surfaces are coated with solution, then drain. Conditioning two or three times will insure that the concentration of titrant is not changed by a stray drop of water.

Why do you rinse a Buret with solution?

Due to the fact, that all burettes are made of glass, it can absorb and remain water on the surface, because of the polarity of the glass and intermolecular forces. Thus, you have to rinse the burette with a solution which must be filled in it, because distilled water change the concentration of the initial solution.

Why is the pipette rinsed with soft drink before filling it to the line with soft drink?

This is done by rinsing down the sides of the flask with water. In this way we avoid adding more titrant than actually necessary to reach the end-point and hence avoid getting a falsely-high volume reading. In this situation the analyte concentration would appear to be more concentrated than it really is.