Laboratory Techniques

Question 1

The beaker is the most common equipment, and it is used for ___, __, and ___ but not ___

Answer 1

heating, stirring, mixing, measure

Question 2

The graduated cylinder is used for basic ___, and has volume markings

Answer 2

measuring

Question 3

test tubes hold small volumes of liquid, and are used for ___, ____ ____, and ____. However it is not used for measuring

Answer 3

mixing, quantitative comparison, storing

Question 4

Droppers are used for drop wise dispensing, and commonly used for ___. it is also known as a __ ___

Answer 4

indicators, pasteur pipette

Question 5

The erlenmeyer flask is used for ___ , ___, and ___. Its shape is better than the beaker for reducing ___. It is not for ___

Answer 5

mixing, stirring, heating, spillage, measuring

Question 6

the volumetric flask has volume markings for __ __ and is most commonly used in ______

Answer 6

accurate measuring, dilutions

Question 7

The boiling flask is for __ and ___, not for measuring, and requires a ___ to hold it upright

Answer 7

swirling, measuring, clamp

Question 8

a bunsen burner produces an __ ___ from a __ __ __

Answer 8

open flame, natural gas source

Question 9

A pH meter balance measures ___ and must be ___

Answer 9

pH, calibrated

Question 10

the digital balance measures the __ of a solid sample

Answer 10

mass

Question 11

burettes are highly ____, long and ___. it is commonly used in ___ experiments and has a ___ that controls how much liquid is released

Answer 11

accurate, graduated, titration, stopcock

Question 12

pipettes are the most highly ___, and is the best tool for measuring ___ volumes

Answer 12

precise, liquid

Question 13

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 __ ___ ___

Answer 13

meniscus, subtracted, reverse numbering system

Question 14

Always use a ___ ____ on the digital mass and ___ before use

Answer 14

weigh boat, tare

Question 15

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 ____

Answer 15

separates, centrifugal force, pellet, supernatant, pipette, decanting

Question 16

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.

Answer 16

drop-by-drop volumes, titrant, titrend, equivalent point, endpoint, colour change

Question 17

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 ___

Answer 17

heat, endothermic, exothermic, styrofoam cup, thermometer

Question 18

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

Answer 18

safety shower, chemical, fumehood, vapors, fumes

Question 19

Fire extinguishers should be used for __ or __ fires and not paper or ___ fires.

Answer 19

solvent, chemical, wood

Question 20

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

Answer 20

burns, chemical fumes, gloves

Question 21

Broken glass should be cleaned with a ___ ___ immediately after being broken and disposed of in the broken glass container

Answer 21

dust painn

Question 22

__ ___ solutions should be dumped down the drain with a lot of water. Water ____ solutions should be disposed of in the correct container

Answer 22

water miscible, immiscible

Question 23

Do not add water to ____ ___. Do not __ or drink in the lab. Do not pipette by ____.

Answer 23

concentrated acid, eat, mouth

Question 24

The closeness of a measured experimental value to the actual literature value

Answer 24

accuracy

Question 25

the consistency of all experimental values

Answer 25

precision

Question 26

Significant figures are used to describe the ___ of a specific measurement. The more there are, the more __

Answer 26

uncertainty, precise

Question 27

____ errors are consistent shifts in one direction of a measurement due to ____ __ or __ ___. Examples including forgetting to ___ a digital balance, or improper ___ of equipment

Answer 27

systematic, faulty equipment, procedural error, tare, calibration

Question 28

____ error varies in either direction due to ____ ___. Examples includes inconsistent reading of the __ or ___ __ in stopping a stopwatch

Answer 28

random, human limitation, meniscus, reaction time

Question 29

___ ___ ____ measures the discrepancy between an experimental and actual value and is given by the formula ______

Answer 29

percent error calculation, percent error = |experimental value - actual value|/actual value x 100