Laboratory Techniques Flashcards
The beaker is the most common equipment, and it is used for ___, __, and ___ but not ___
heating, stirring, mixing, measure
The graduated cylinder is used for basic ___, and has volume markings
measuring
test tubes hold small volumes of liquid, and are used for ___, ____ ____, and ____. However it is not used for measuring
mixing, quantitative comparison, storing
Droppers are used for drop wise dispensing, and commonly used for ___. it is also known as a __ ___
indicators, pasteur pipette
The erlenmeyer flask is used for ___ , ___, and ___. Its shape is better than the beaker for reducing ___. It is not for ___
mixing, stirring, heating, spillage, measuring
the volumetric flask has volume markings for __ __ and is most commonly used in ______
accurate measuring, dilutions
The boiling flask is for __ and ___, not for measuring, and requires a ___ to hold it upright
swirling, measuring, clamp
a bunsen burner produces an __ ___ from a __ __ __
open flame, natural gas source
A pH meter balance measures ___ and must be ___
pH, calibrated
the digital balance measures the __ of a solid sample
mass
burettes are highly ____, long and ___. it is commonly used in ___ experiments and has a ___ that controls how much liquid is released
accurate, graduated, titration, stopcock
pipettes are the most highly ___, and is the best tool for measuring ___ volumes
precise, liquid
Always read at the bottom of the _____. On a burette, the numbers are upside down and the number read is the amount ___ from the total to get the amount of volume left. This is the __ ___ ___
meniscus, subtracted, reverse numbering system
Always use a ___ ____ on the digital mass and ___ before use
weigh boat, tare
The centrifuge ___ parts of a mixture by spinning fast, creating __ __. This forces the the solid components down at the bottom as a ___ and leaves the liquid components on top as a ____. Then the two can be separated via a ___ or by ____
separates, centrifugal force, pellet, supernatant, pipette, decanting
A titration reaction is performed by delivering ______ _____ of the _____ to the ____. The ___ point is the point at which the titrant and titrend have completely reacted, while the ___ is the point in which a __ ___ occurs.
drop-by-drop volumes, titrant, titrend, equivalent point, endpoint, colour change
A calorimetry experiment is performed to observe how much ___ is absorbed or released during an experiment. This helps determine if the reaction is __ or ___. The set up requires a ____ __ and a ___
heat, endothermic, exothermic, styrofoam cup, thermometer
The ___ ___ is used if something is caught on fire, the eye wash station is used in the case of ___ in the eyes. The ___ is used to provide proper ventilation in a closed space and minimizes one’s exposure to harmful __ or __ that one may be working with
safety shower, chemical, fumehood, vapors, fumes
Fire extinguishers should be used for __ or __ fires and not paper or ___ fires.
solvent, chemical, wood
lab coats should be worn to prevent chemical ___, while safety goggles should be worn to prevent your eyes from __ ___ getting into them. Safety ___ should only be used if you are working with harmful chemicals
burns, chemical fumes, gloves
Broken glass should be cleaned with a ___ ___ immediately after being broken and disposed of in the broken glass container
dust painn
__ ___ solutions should be dumped down the drain with a lot of water. Water ____ solutions should be disposed of in the correct container
water miscible, immiscible
Do not add water to ____ ___. Do not __ or drink in the lab. Do not pipette by ____.
concentrated acid, eat, mouth
The closeness of a measured experimental value to the actual literature value
accuracy
the consistency of all experimental values
precision
Significant figures are used to describe the ___ of a specific measurement. The more there are, the more __
uncertainty, precise
____ errors are consistent shifts in one direction of a measurement due to ____ __ or __ ___. Examples including forgetting to ___ a digital balance, or improper ___ of equipment
systematic, faulty equipment, procedural error, tare, calibration
____ error varies in either direction due to ____ ___. Examples includes inconsistent reading of the __ or ___ __ in stopping a stopwatch
random, human limitation, meniscus, reaction time
___ ___ ____ measures the discrepancy between an experimental and actual value and is given by the formula ______
percent error calculation, percent error = |experimental value - actual value|/actual value x 100
