I have attached here with 104 slides about Laboratory equipments and uses, Common laboratory techniques, Substances available in a laboratory (I. Solid II. Liquids III.Metals) Safety symbols and Lab safety
Importance of Activity based learning in Science Subject.
This slide contains many aspects which should be followed to make a class interactive and promote effective learning based upon different types of learners.
Role of science lab, exhibition, quiz, debate, field trips to learning of student.
The 5E's is an instructional model based on the constructivist approach to learning, which says that learners build or construct new ideas on top of their old ideas. The 5 E's can be used with students of all ages, including adults. Each of the 5 E's describes a phase of learning, and each phase begins with the letter "E": Engage, Explore, Explain, Elaborate, and Evaluate. The 5 E's allows students and teachers to experience common activities, to use and build on prior knowledge and experience, to construct meaning, and to continually assess their understanding of a concept.
In this model of learning, students learn in five sequential phases i.e. Engagement- Exploration-Explanation-Elaboration-Evaluation.
Importance of Activity based learning in Science Subject.
This slide contains many aspects which should be followed to make a class interactive and promote effective learning based upon different types of learners.
Role of science lab, exhibition, quiz, debate, field trips to learning of student.
The 5E's is an instructional model based on the constructivist approach to learning, which says that learners build or construct new ideas on top of their old ideas. The 5 E's can be used with students of all ages, including adults. Each of the 5 E's describes a phase of learning, and each phase begins with the letter "E": Engage, Explore, Explain, Elaborate, and Evaluate. The 5 E's allows students and teachers to experience common activities, to use and build on prior knowledge and experience, to construct meaning, and to continually assess their understanding of a concept.
In this model of learning, students learn in five sequential phases i.e. Engagement- Exploration-Explanation-Elaboration-Evaluation.
5 E Model lesson plan in biology- Photosynthesismahindravada
5 E model is a widely used method of teaching using the constructivist approach. A lesson plan is presented here for a
5 E model has been presented here taking the example of photosynthesis. The activities in each stage of the 5 stages have been explained.
It discuss about what is community resources, what all comes undercommunity resources, Zoological garden, botanical garden, principles of botanical garden, Eco park, Aquarium, science fair, field trip and ADVANTAGES OF COMMUNITY RESOURCES
I have attached here with 104 pages of PDF about Laboratory equipments and uses, Common laboratory techniques, Substances available in a laboratory (I. Solid II. Liquids III.Metals) Safety symbols and Lab safety
5 E Model lesson plan in biology- Photosynthesismahindravada
5 E model is a widely used method of teaching using the constructivist approach. A lesson plan is presented here for a
5 E model has been presented here taking the example of photosynthesis. The activities in each stage of the 5 stages have been explained.
It discuss about what is community resources, what all comes undercommunity resources, Zoological garden, botanical garden, principles of botanical garden, Eco park, Aquarium, science fair, field trip and ADVANTAGES OF COMMUNITY RESOURCES
I have attached here with 104 pages of PDF about Laboratory equipments and uses, Common laboratory techniques, Substances available in a laboratory (I. Solid II. Liquids III.Metals) Safety symbols and Lab safety
Beaker
Beakers hold solids or liquids that will not release gases when reacted or are unlikely to splatter if stirred or heated.
Beaker Tongs
Beaker tongs are used to move beakers containing hot liquids.
Erlenmeyer Flask
Erlenmeyer flasks hold solids or liquids that may release gases during a reaction or that are likely to splatter if stirred or heated.
Florence Flask
Rarely used in first year Biochemistry, it is used for the mixing of chemicals. Narrow neck prevents splash exposure.
Graduated Cylinder
A graduated cylinder is used to measure volumes of liquids.
Test Tubes
Test Tube Holder
A test tube holder is useful for holding a test tube which is too hot to handle.
Test Tube Brushes
Test tube brushes are used to clean test tubes and graduated cylinders.
Forcing a large brush into a small test tube will often break the tube.
Test Tube Racks
Test tube racks are for holding and organizing test tubes on the laboratory counter.
After washing flip test tube over on wooden peg to dry.
Rubber Stoppers
Rubber stoppers are used to close containers to avoid spillage or contamination.
Glass Stir Rod
A glass rod is used to manually stir solutions. It can also be used to transfer a single drop of a solution.
Forceps
Forceps (or tweezers) are used to pick up small objects.
Funnel
A funnel is used to aid in the transfer of liquid from one vessel to another.
Watch Glass
A watch glass is used to hold a small amount of solid, such as the product of a reaction.
Wash Bottle
A wash bottle has a spout that delivers a wash solution to a specific area. Distilled water is the only liquid that should be used in a wash bottle.
Weighing Boat
Weighing boats are used to weigh solids that will be transferred to another vessel.
Bunsen Burner
Bunsen burners are used for the heating of nonvolatile liquids and solids.
Evaporating Dish
The evaporating dish is used for the heating of stable solid compounds and elements.
Crucible
Crucibles are used for heating certain solids, particularly metals, to very high temperatures.
Clay Triangle
The clay triangle is used as a support for porcelein crucibles when being heated over a Bunsen burner.
Crucible Tongs
For handling hot crucibles; also used to pick up other hot objects. NOT to be used for picking up beakers!
Ringstands and their Components
Ringstand
Ringstands are a safe and convenient way to perform reactions that require heating using a Bunsen burner.
Ringstands and their ComponentsUtility Clamps
Utility clamps are used to secure test tubes, distillation columns, and burets to the ringstand.
Ringstands and their ComponentsWire Gauze
Wire gauze sits on the iron ring to provide a place to stand a beaker.
Ringstands and their ComponentsDouble Buret Clamps
Double Buret clamps are used to burets – long graduated tubes used in titration.
Triangular File
Triangular files are used primarily to cut glass rod, a skill that your instructor will share with you when it becomes useful.
Litmus Paper
Red litmus paper is used to identify ba
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Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
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Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
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The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
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Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
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June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
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Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
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• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
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2. contents
I. Laboratory equipments and uses
II. Common laboratory techniques
III. Substances available in a laboratory
I. Solid
II. Liquids
III. Metals
IV.Safety symbols
V. Lab safety
3. 1.Laboratory equipments and its
uses
Beaker
Usage-Beakers are useful as a reaction
container or to hold liquid or solid samples.
They are also used to catch liquids from
titrations and filtrates from filtering
operations.
4. Volumetric flasks
Usage- It is used to
make up a solution to
a known volume.
Volumetric flasks
measure volumes
much more precisely
than beakers and
Erlenmeyer flasks
6. Boiling tube
A boiling tube is a small cylindrical
vessel used to strongly heat
substances in the flame of a Bunsen
burner. A boiling tube is essentially a
scaled-up test tube, being about 50%
larger.
7. An ignition tube is a piece of
laboratory equipment.
Usage - It is a laboratory tube
used much in the same way as a
boiling tube except not being as large
and thick-walled.
It is primarily used to hold small
quantities of substances which are
undergoing direct heating by a Bunsen
burner or other heat source.
Ignition tube
8. Conical flask
Conical flasks are
widely used in
chemistry laboratories
for holding liquids and
mixing them by swirling.
9. The volumetric flask is used for
measuring accurate volumes of liquid
materials for laboratory experiments.
They are favored when available
because they are more accurate than
graduated cylinders and beakers, which
are other pieces of equipment that
are used to measure liquids.
Volumetric flask
10. Measuring cylinder
A graduated cylinder (or measuring
cylinder) is a piece of laboratory
glassware used to measure the
volume of liquids.
It is used to accurately measure the
volume of chemicals for use in
reactions..
11. Round bottom flask
A glass flask used in a laboratory for
holding chemical liquids and solutions,
which has a spherical shape for uniform
heating, and one or more long cylindrical
necks.
12. Flat bottom flask
•A flat bottomed flask is
used in settings where
the flask will be set on a
level surface, rather than
in a clamp or bowl.
•On the other hand,
a flask with a round
bottom will either sit in a
bowl or be suspended
above a surface using a
clamp.
13. Reagent bottles, also known as
media bottles or graduated bottles, are
containers made of glass,
plastic, borosilicate or related substances,
and topped by special caps or stoppers and
are intended to contain chemicals in liquid
or powder form for laboratories and stored
in cabinets or on shelves.
Reagent bottle
14. An alcohol lamp is used for heating,
sterilization, and combustion in a
laboratory.
The alcohol lamp
uses ethyl alcohol or spirit as a fuel.
Spirit lamp
15. Test tube holder
A test tube holder is used to hold test
tubes.
It is used for holding a test tube in place
when the tube is hot or should not be
touched.
16. Tripod
•A tripod allows you to capture a longer
exposure by using a slower shutter speed
of up to several seconds.
•This helps to minimise the risk of any
movement.
•While capturing a long exposure the use of
a tripod will allow much more light to enter
the camera than would be possible
if you were taking a picture hand held.
18. Burette
usage- Burets are for
addition of a precise volume
of liquid. The volume of
liquid added can be
determined to the nearest
0.01 ml with practice.
19. Pippete
A pipette (sometimes spelled pipet) is a
laboratory tool commonly used in
chemistry, biology and medicine to
transport a measured volume of liquid,
often as a media dispenser.
20. Funnel
Usage- Glass Funnels are for
funneling liquids from one container
to another or for filtering when
equipped with filter paper
21. Decicator
A common use for desiccators is to
protect chemicals which are hygroscopic
or which react with water from humidity.
Desiccators are
sealable enclosures
containing desiccants
used for preserving
moisture-sensitive
items such as cobalt
chloride paper for
another use.
22. The Bunsen burner is now a
very important tool in modern
chemistry laboratories.
It can burn a number of types of fuel,
and produces a single clean and hot
flame.
The Bunsen burner has a valve for
gas intake, and a needle valve that
allows precise control of the amount of
air that mixes with the fuel.
Bunsen Burner
23. Watch class
A watch glass is a circular concave
piece of glass used in chemistry as a
surface to evaporate a liquid, to hold
solids while being weighed, for heating
a small amount of substance and as a
24. Forcep
Forceps are a handheld, hinged
instrument used for grasping and
holding objects
25. In laboratories, spatulas and
microspatulas are small
stainless steel utensils, used for
scraping, transferring, or applying
powders and paste like chemicals or
treatments.
Many spatula brands are also
resistant to acids, bases, heat, and
solvents, which make them ideal for
use with a wide range of compound.
Spectula
26. Stand
A retort stand, sometimes called a
clamp stand or a ring stand, is a
piece of scientific equipment to which
clamps can be attached to hold other
pieces of equipment and glassware –
for instance, burettes, test tubes and
flasks.
27. A wire gauze is a sheet of thin metal
that has net-like patterns or a wire
mesh. Wire gauze is placed on the
support ring that is attached to the
retort stand between the Bunsen
burner and the glassware to support
the beakers, flasks, or other glassware
during heating.
Wire gouge
28. They can be used...
as a water pick
as a parts washer
as a water pistol
as a dye/paint dispenser
as an air duster (alternative to canned
air)
for cleaning under rim of toilet (remove
inside tube, fill with vinegar and use
upside down)
for pre-treating stains in the laundry (use
liquid detergent/soap/dish soap thinned
with water or vinegar)
Wash bottle
29. Funnel
Laboratory tongs are large pincers
for grasping and lifting vessels of heat-
resistant material used in high
temperature chemical reactions.
Tongs differ in shape are designed to
pick up laboratory items including,
hot evaporating dishes, beakers,
crucibles, and
other laboratory apparatuses
30. Tongs
Laboratory tongs are large pincers for
grasping and lifting vessels of heat-
resistant material used in high
temperature chemical reactions.
Tongs differ in shape are designed to
pick up laboratory items including, hot
evaporating dishes, beakers, crucibles,
and other laboratory apparatuses
31. Biologists, medical workers, and students
love to use microscopes in their projects.
This common piece of equipment is
present in almost every laboratory.
It is used to magnify anything that is tiny
for our eyes to 1000 of times its normal
size.
It can also show the slightest details of a
thing, even the invisible cells of plants
and skin.
Microscope
32. Parts of microscope
Eyepiece: The lens the viewer looks
through to see the specimen. The
eyepiece usually contains a 10X or
15X power lens.
33. Diopter Adjustment: Useful as a
means to change focus on one
eyepiece so as to correct for any
difference in vision between your two
eyes.
Body tube (Head): The body tube
connects the eyepiece to the objective
lenses.
Arm: The arm connects the body tube
to the base of the microscope.
Coarse adjustment: Brings the
specimen into general focus.
34. Fine adjustment: Fine tunes the focus and
increases the detail of the specimen.
Nosepiece: A rotating turret that houses the
objective lenses. The viewer spins the
nosepiece to select different objective lenses.
Objective lenses: One of the most important
parts of a compound microscope, as they are
the lenses closest to the specimen.
A standard microscope has three, four, or five
objective lenses that range in power from 4X
to 100X. When focusing the microscope, be
careful that the objective lens doesn’t touch
the slide, as it could break the slide and
destroy the specimen
35. Specimen or slide: The specimen is
the object being examined. Most
specimens are mounted on slides, flat
rectangles of thin glass.
The specimen is placed on the glass
and a cover slip is placed over the
specimen.
This allows the slide to be easily
inserted or removed from the
microscope.
It also allows the specimen to be
labeled, transported, and stored
36. Stage: The flat platform where the slide
is placed.
Stage clips: Metal clips that hold the
slide in place.
Stage height adjustment (Stage
Control): These knobs move the stage
left and right or up and down.
Aperture: The hole in the middle of the
stage that allows light from the
illuminator to reach the specimen.
On/off switch: This switch on the base
of the microscope turns the illuminator
off and on.
37. Triple beam balance Read
Usage -The triple beam
balance is used to measure masses
very precisely; the reading error is 0.05
gram.
With the pan empty, move
the three sliders on the three beams to
38. Chemical balance is a delicate
instrument which is used to weigh small
amounts of substances accurately up to
the fourth place of decimal.
It is necessary in volumetric analysis as
the substances used to prepare standard
solutions are weighed.
Chemical balance
39. Digital balance
The digital mass balances in the General
Chemistry labs are very sensitive
instruments used for weighing
substances to the milligram (0.001 g)
level.
Use containers when weighing
41. Reading a Meniscus
In all volumetric glassware (pipet, buret,
volumetric flasks, graduated cylinder,
etc.), it is necessary to read the level of
a liquid. A liquid in a small-diameter
container will form a meniscus or curve
at the surface of the liquid.
Usually this meniscus curves downward
to a minimum at the center.
To read the level of the liquid properly
the eye should be at the same
level as the bottom of the meniscus.
42. Sometimes a white card or a white card
with a black mark on it will help a person
to see the meniscus clearly.
For volumetric flasks and transfer pipets,
the volume of the glassware is exact
when the bottom of the meniscus is even
with the etched line.
In a graduated cylinder or a buret, the
volume is read from the graduations
etched on the glass.
To read the volume correctly, visualize
the distance between the tenths of
milliliter marks as divided into ten equal
amounts.
The volume is then found by reading the
number of tenths of milliliters and
estimating hundredths of milliliters
43. Care of Reagents
The reagents used by all of the students
can be contaminated by one careless
student. Never put anything back into
the reagent bottle. A certain amount of
liquid can be obtained in several ways.
1) Pour from the reagent bottle into a
beaker and draw up the liquid into a
pipette from the beaker.
2) Pour from the beaker into a graduated
cylinder to within 0.1 ml of the desired
amount, adding the last drop with an
eyedropper filled from a beaker.
44. Only use appropriately labeled spatulas
for each reagent bottle.
Pour the solid into a beaker, onto
weighing paper, or into a weigh boat.
Never pour excess back into the bottle.
Reagents are to remain on the plastic on
the center bench. This will
1)prevent spills and accidents from
occurring at your work area,
2)save time for everyone because all of
the chemicals will be relatively easy to find
in a central location, and
3)make clean-up easier if a spill does
occur. When you are finished using a
chemical, replace the lid! A mix-up of lids
could also contaminate an expensive
45. Below is a simple outline that will help you to
use the balance more effectively, safely, and
will assist in reducing the speed at which the
Stockroom Manager’s hair is turning
prematurely gray.
Select a suitable container (usually a weigh
boat, weigh paper, or glassware) to weigh the
chemical in.
Care and Use of Balances
46. Place the container on the balance
pan and replace the balance cover.
Replacing the balance cover will
greatly reduce fluctuations in the
balance reading!
Allow the balance reading to stabilize.
Zero the balance by pressing the
TARE button or bar which is located at
the front of the balance. DO NOT hold
down the tare button/bar! This will
cause the balance to change units and
you may end up weighing your
chemical in units other then grams
which will cause your data to be in
error!
47. Remove the balance cover and carefully
transfer the desired chemical to the container.
If you use a spatula, use only a clean, dry
spatula for obtaining dry chemicals. If you
should spill a chemical on the balance pan,
use the brush that is attached to the balance
to clean the balance pan IMMEDIATELY!
Chemicals left on the balance pan will
corrode the pan.
Replace the balance cover and allow the
balance reading to stabilize.
In the event you weigh out too much
chemical, remove the excess to a secondary
container. NEVER return a chemical to its
original container! There will always be some
left over. Try to find someone else who
needs it before disposing of it.
48. Discard chemicals as directed in each
experiment (See the Safety and
Disposal section for each experiment).
Record the balance reading in your
notebook.
Remove the container from the
balance pan and replace the balance
cover. 10. Replace the appropriate lids
on all reagent bottles when finished.
49. Titration
The titration procedure is
accomplished by adding small
amounts of one reactant to a
beaker or flask containing the
other until the reaction is
completed.
In an acid-base reaction, the
reaction is complete when the
amount of acid equals the
amount of base.
The experimenter is aware of
this condition by the change in
pH that occurs. The change
in pH is indicated by a color
change of an indicator or by a
50. In other types of reactions, the
completion of the reaction is usually also
indicated by a color change. Titrations
are often accomplished using a burette.
volume added is the final volume minus
initial volume.
A small amount (~ 5 - 10 ml) of the
solution is used to rinse a clean burette.
The rinse solution is discarded. The
burette is filled to just below the zero
mark.
The liquid level is read and recorded as
the initial volume.
51. A burette has zero at the top
Small amounts of the solution are
allowed to flow out of the burette into the
flask by turning the stopcock.
Often localized color changes will be
evident for a short period of time.
Mixing the solution by swirling the flask
will usually cause the color to return to
the original color.
As the color lasts longer, the next
addition of solution needs to be smaller.
Close to the endpoint (reaction
completion), the additions are one drop
at a time.
When the endpoint is reached, the liquid
level is read and recorded as the final
52. Using A Bunsen Burner
Lighting the Bunsen burner
- Make sure the rubber
tubing is connected to the
Bunsen burner and the gas
jet.
Turn the gas valve until it is
parallel to the gas jet.
You should be able to hear
the gas flow. Use a flint
striker to cause a spark and
53. Adjusting the Bunsen burner - First, adjust
the height of the flame using the gas valve at
the bottom of the burner.
For a clean burning flame, more air is
required than is available from the gas
exhaust.
The air vents can be adjusted to produce an
inner blue cone in the flame with no yellow
tip.
Too little air produces a sooty, orange-yellow
tipped flame that is quite noisy.
Too much air supply may cause the flame to
separate from the burner and even blow itself
out.
The ideal working flame is bluish-green with a
54. Chemical substances available
in the science laboratory
Solid substances
◦ Salts
◦ Chemical substances
Liquid form substances
◦ Acids
◦ Base
◦ Alcohol
Metals
95. Lab safety
Why is this the most important rule? If you
don't follow it:
You endanger yourself and others in the
lab.
You could easily ruin your experiment.
You put the lab at risk of an accident,
which could damage equipment as well as
harm people.
You could get suspended
96. Rules to follow
Dress for the Lab
Dress for the lab. This is a safety rule
because your clothing is one of your best
forms of protection against an accident.
For any science lab, wear covered
shoes, long pants, and keep your hair up
so it can't fall into your experiment or a
flame.
Make sure you wear protective gear, as
needed. Basics include a lab coat and
safety goggles. You may also need
gloves, hearing protection, and other
items, depending on the nature of the
97. Know the
Location
of Safety
Equipment In the event something goes wrong, it's
important to know the location of the
safety equipment and how to use it. It's a
good idea to periodically check
equipment to make sure it is in working
order. For example, does water actually
come out of the safety shower? Does the
water in the eye wash look clean?
Not sure where safety equipment is
located? Review lab safety signs and
look for them before starting an
experiment.
98. Don't Eat or Drink
in the Laboratory
Don't eat or drink in the science
laboratory.
Don't store your food or beverages in
the same refrigerator that contains
experiments, chemicals, or cultures.
99. Don't Taste or Sniff Chemicals
Not only should you not bring in food
or drinks, but you shouldn't taste or
smell chemicals or biological
cultures already in the lab.
Tasting or smelling some chemicals
can be dangerous or even deadly.
100. Don't Play Mad Scientist in the
Laboratory
Another important safety rule is to act
responsibly in the lab — don't play
Mad Scientist, randomly mixing
chemicals to see what happens. The
result could be an explosion, fire,
or release of toxic gases.
Similarly, the laboratory is not the
place for horseplay. You could break
glassware, annoy others, and
potentially cause an accident.
101. Dispose of Lab Waste
Properly
One important laboratory safely rule is
to know what to do with your
experiment when it's over. Before you
start an experiment, you should know
what to do at the end. Don't leave your
mess for the next person to clean up.
102. Accidents happen, but you can do your
best to prevent them and have a plan to
follow when they occur. Most laboratories
have a plan to follow in the event of an
accident.
One particularly important safety rule is to
tell a supervisor if and when an accident
occurs.
Know What to Do With Lab
Accidents
103. Don't Experiment on Yourself
The premise of many a science fiction
movie starts with a scientist
conducting an experiment on him or
herself.
More than likely, whatever you
accomplish will be at great personal
risk.
You need data on multiple
subjects to draw conclusions,
but using yourself as a subject and
self experimenting is dangerous, not
to mention bad science.