Techniques 1-7 Flashcards
What are the four sources of fire ignition in a laboratory?
Open flames, hot surfaces, faulty electrical equipment, and chemicals. Preventing the union of these with an oxidizing agent will help to prevent most fires.
Where should you avoid having Bunsen burners?
Avoid having bunsen burners near low-boiling point liquids, especially pentane, diethyl ether, or other low-bp organic solvents (try to be more than 10 ft away)
How should you avoid fires with hot plates?
Remove a hot plate before pouring or mixing any organic solvents, as the vapors may be ignited.
How should you properly break a a glass rod?
First, score the glassware to be broken on one side of the tube with a file, then wet the score line with a drop of water. Then hold in a paper towel, and break by pulling the ends toward you with the score mark facing away.
How should you insert glass tubes into stoppers?
By first wetting the end of the glass tube with water, then hold the tube with a towel close to the end near the stopper, and rotate it slowly and firmly into the stopper.
How should you use a fume hood?
Always open it to the optimal level before use, and make sure the hood is turned on before you use it. Most experiments in organic chemistry should be conducted in a fume hood.
What type of gloves should you use for an experiment?
You should find out ahead of time which types of gloves will offer maximum protection for the experiment you are doing.
How should you temporarily store organic solvents with a low boiling point?
In an erlenmeyer flask with a cork on top.
What is the goal of green chemistry?
To switch to using reactions or reagents that require less quantity, are less damaging to the environment, and require less energy to use.
How does stirring affect reaction rate?
It increases in by increasing the solubility of otherwise less soluble compounds due to the increased surface area interaction of the two.
What are reaction efficiency, percent yield, and atomic economy?
Atomic economy is how much atomic mass of the reactants are actually present in the products, percent yield is the ratio of products:byproducts you get, and reaction efficiency is these two multiplied together.
What different kind of hazardous waste containers are contained in an organic chemistry lab?
Liquid halogenated waste, aqueous waste, which is neutralized acidic or basic solution, flammable waste, and solid waste.
When are plastic pipettes not suitable for use?
When dealing with liquid halogenated solutions, otherwise they are excellent and impervious to chemical damage.
When should boiling stones be added, and how many are necessary?
Before heating the liquid, and typically one or two boiling stones is sufficient.
What is bumping?
The creation of large bubbles during boiling which can explode and cause spills or damage and pose a hazard, and it can be avoided with the use of a magnetic stir bar or boiling stones.
