Unit 1 NotesUnit 1 Notes

SafetySafety

Unit 1 Learning Targets Unit 1 Learning Targets 1.1. I can locate, identify, and use all of the safety I can locate, identify, and use all of the safety

features in the classroom.features in the classroom.2.2. I can use a NFPA label to identify the degree I can use a NFPA label to identify the degree

of harmfulness of a given chemical.of harmfulness of a given chemical.3.3. I can locate and use a MSDS.I can locate and use a MSDS.4.4. I can identify different pieces of chemical I can identify different pieces of chemical

equipment and what each piece is used for.equipment and what each piece is used for.5.5. I can use proper techniques to light a Bunsen I can use proper techniques to light a Bunsen

burner.burner.6.6. I can explain the difference between a I can explain the difference between a

scientific theory and a scientific law.scientific theory and a scientific law.

Target 1Target 1

I can locate, identify, and use all of the I can locate, identify, and use all of the safety features in the classroom.safety features in the classroom.

Safety GearSafety Gear Safety GogglesSafety Goggles Lab ApronsLab Aprons These are to be worn These are to be worn

at ALL times during at ALL times during EVERY chemistry lab. EVERY chemistry lab.

Failure to do this will Failure to do this will result in removal from result in removal from the lab and an the lab and an administrative referral.administrative referral.

Locating Safety Locating Safety EquipmentEquipment

Broken glassware Broken glassware containercontainer

Ventilation HoodVentilation Hood MSDSMSDS Emergency Gas Emergency Gas

Shutoff ButtonShutoff Button Fire ExtinguisherFire Extinguisher Emergency EyewashEmergency Eyewash Goggles/ApronsGoggles/Aprons

What are they used for?What are they used for? Broken glassware container – You don’t Broken glassware container – You don’t

want to put anyone in danger while want to put anyone in danger while emptying the trashemptying the trash

Ventilation (fume) hood – the fans suck up Ventilation (fume) hood – the fans suck up the air so that you don’t inhale toxic fumes.the air so that you don’t inhale toxic fumes.

MSDS – have safety information about a MSDS – have safety information about a chemical.chemical.

Emergency gas button – if a flame gets Emergency gas button – if a flame gets close to the gas nozzle, hit this button to close to the gas nozzle, hit this button to turn off the gas and prevent an explosion.turn off the gas and prevent an explosion.

What are they used for?What are they used for?

Fire extinguisher – extinguish fires…Fire extinguisher – extinguish fires… Emergency eyewash – to rinse your eyes Emergency eyewash – to rinse your eyes

if you get a chemical in them.if you get a chemical in them. Goggles – protect your eyes from Goggles – protect your eyes from

chemicalschemicals Lab aprons – protect your clothing from Lab aprons – protect your clothing from

chemicals.chemicals.

How do they work?How do they work?

Add how to use the following safety Add how to use the following safety equipment to your notes:equipment to your notes:

Ventilation (fume) hoodVentilation (fume) hood Emergency gas buttonEmergency gas button Fire extinguisherFire extinguisher Emergency eyewashEmergency eyewash

Let’s Practice with Let’s Practice with some WS’s!some WS’s!Laboratory Safety WS, Safety Laboratory Safety WS, Safety Equipment WS, Safety Scavenger Equipment WS, Safety Scavenger HuntHunt

Target 2Target 2

I can use a NFPA label to identify I can use a NFPA label to identify the degree of harmfulness of a given the degree of harmfulness of a given chemical.chemical.

NFPA LabelsNFPA Labels

National Fire National Fire Prevention AgencyPrevention Agency

It’s a color-coded It’s a color-coded label found on each label found on each chemical.chemical.

Each section Each section indicates a certain indicates a certain hazard about the hazard about the chemical.chemical.

The colored sectionsThe colored sections

Reading the labelReading the label

Let’s Practice with Let’s Practice with a WS!a WS!NFPA Labels WS!NFPA Labels WS!

Target 3Target 3

I can locate and use a MSDS.I can locate and use a MSDS.

MSDSMSDS Material Safety Data Material Safety Data

SheetsSheets Has many sections that Has many sections that

contain information contain information about the chemical.about the chemical.

Section numbers may Section numbers may vary depending on the vary depending on the brand/type of MSDS.brand/type of MSDS.

Time for WS’s and Time for WS’s and an activity!an activity!MSDS Sections WS, MSDS Practice MSDS Sections WS, MSDS Practice WS, Material Safety Data Sheets WS, Material Safety Data Sheets WS, Oops! I spilled it again activity!WS, Oops! I spilled it again activity!

Target 4Target 4

I can identify different pieces of I can identify different pieces of chemical equipment and what each chemical equipment and what each piece is used for.piece is used for.

Erlenmeyer FlaskErlenmeyer Flask

The Erlenmeyer flask is the most The Erlenmeyer flask is the most common flask in the chemistry lab. It is common flask in the chemistry lab. It is used to contain reaction solutions. used to contain reaction solutions.

PipettePipette Like an eyedropper, it is used to add Like an eyedropper, it is used to add

small amounts of liquid. small amounts of liquid. Some have measurements (0.5 mL, 1 Some have measurements (0.5 mL, 1

mL) so that you can measure and add mL) so that you can measure and add small amounts.small amounts.

Graduated Cylinder Graduated Cylinder Used to make accurate measurements of Used to make accurate measurements of

liquid volumes. The bumper on larger liquid volumes. The bumper on larger cylinders is to prevent breakage if tipped cylinders is to prevent breakage if tipped over. Keep it near the top.over. Keep it near the top.

BeakerBeaker Beakers are the most versatile glassware Beakers are the most versatile glassware

in the lab and can be used for just about in the lab and can be used for just about anything. The volume measurements on anything. The volume measurements on beakers should be used only for beakers should be used only for “ballpark” estimates.“ballpark” estimates.

Beaker brushBeaker brush

Used to clean beakers.Used to clean beakers. They are attached to every sink in the They are attached to every sink in the

room.room.

FunnelFunnel Besides helping to direct the pour of Besides helping to direct the pour of

liquids into narrow openings, you can liquids into narrow openings, you can also use filter paper with the funnel to also use filter paper with the funnel to filter out solids from a liquid.filter out solids from a liquid.

Test tubesTest tubes

Test tubes: Used to mix or heat small Test tubes: Used to mix or heat small amounts of chemicals/solutions.amounts of chemicals/solutions.

Test tube brushTest tube brush

Cleans test tubesCleans test tubes There is one attached to every sink in the There is one attached to every sink in the

room.room.

Test tube holderTest tube holder

Used to hold test tubes for short periods Used to hold test tubes for short periods of “gentle” heating.of “gentle” heating.

Test tube clampTest tube clamp

When attached to the ring stand, this When attached to the ring stand, this clamp is used to hold a large test tube clamp is used to hold a large test tube above the lab table. above the lab table.

Ring standRing stand You can clamp things (such as the metal You can clamp things (such as the metal

ring, test tube clamp, etc) onto it in order ring, test tube clamp, etc) onto it in order to hold glassware over the lab table.to hold glassware over the lab table.

Wire gauzeWire gauze Used as a support for beakers when Used as a support for beakers when

placed across a metal ring.placed across a metal ring.

StrikerStriker Used to light a Bunsen burner. Used to light a Bunsen burner. It is NOT a toy or noisemaker during lab It is NOT a toy or noisemaker during lab

(you will wear down the flint).(you will wear down the flint).

Bunsen burner & tubingBunsen burner & tubing

Provides a flame for heating substances.Provides a flame for heating substances. Tubing directs gas into the Bunsen Tubing directs gas into the Bunsen

burner.burner.

Metal ringMetal ring

The metal ring can be used with wire The metal ring can be used with wire gauze to support a beaker or flask above gauze to support a beaker or flask above the lab table.the lab table.

ScupulaScupula Used to scoop solid chemicals out of a Used to scoop solid chemicals out of a

container. container. Tip the container sideways with the beaker Tip the container sideways with the beaker

directly under the container. directly under the container. It’s always better to take several small It’s always better to take several small

scoops than one large scoop. You are less scoops than one large scoop. You are less likely to spill this way, and we don’t want to likely to spill this way, and we don’t want to spill any chemicals!spill any chemicals!

Test tube rackTest tube rack

Test tube rack: holds many test tubes at Test tube rack: holds many test tubes at once so you can do multiple tests without once so you can do multiple tests without breaking them.breaking them.

Spot plateSpot plate

Used as a space to carry out many tiny Used as a space to carry out many tiny reactions (a few drops of each chemical).reactions (a few drops of each chemical).

Let’s get Let’s get acquainted!acquainted!Lab drawer checklistLab drawer checklist

Target 5Target 5

I can use proper techniques to light I can use proper techniques to light a Bunsen burner.a Bunsen burner.

Bunsen burners varyBunsen burners vary

Other Items We Might Other Items We Might UseUse

Ring standRing stand(left)(left)

Metal RingMetal Ring(right)(right)

What NOT to do!What NOT to do! Never light a Bunsen Never light a Bunsen

burner on the ring stand!burner on the ring stand! You never know how high You never know how high

the flame will be when it the flame will be when it ignites and it could spread ignites and it could spread out when it hits the metal out when it hits the metal ring and come right at ring and come right at YOU!!YOU!!

Never light a Bunsen Never light a Bunsen burner with flammable burner with flammable materials nearby! (for materials nearby! (for obvious reasons)obvious reasons)

Blue = Hotter!Blue = Hotter!

We want a blue We want a blue flame rather than an flame rather than an orange flame.orange flame.

This is because blue This is because blue flames are hotter flames are hotter than orange flames.than orange flames.

Blue flames are also Blue flames are also more steady and not more steady and not as “wavy”.as “wavy”.

So what makes it blue?So what makes it blue? More air getting into the tube means that it More air getting into the tube means that it

will be less orange and more blue. will be less orange and more blue. If the air ports are closed, you get orange. If the air ports are closed, you get orange. The more open the air ports are, the bluer The more open the air ports are, the bluer

it will be, but be careful…it will be, but be careful… You don’t want to make it come apart – the You don’t want to make it come apart – the

flame would be out of control!flame would be out of control! If that were to happen (ACCIDENTALLY), If that were to happen (ACCIDENTALLY),

what should you do?!?what should you do?!?

Time for an Time for an activity!activity!Let’s light a Bunsen burner!Let’s light a Bunsen burner!

Target 6Target 6

I can explain the difference between a I can explain the difference between a scientific theory and a scientific law.scientific theory and a scientific law.

Wording Matters!Wording Matters! Wording is very important in science.Wording is very important in science. For example: For example: theorytheory, law, and hypothesis , law, and hypothesis

don’t all mean the same thing.don’t all mean the same thing. Outside of science, you might say Outside of science, you might say

something is “just a theory”, meaning it’s something is “just a theory”, meaning it’s an idea that may or may not be an idea that may or may not be truetrue. .

In science, a theory is an explanation that In science, a theory is an explanation that generallygenerally is accepted to be true. is accepted to be true.

Here’s a closer look at these important, Here’s a closer look at these important, commonly misused terms.commonly misused terms.

HypothesisHypothesis A hypothesis is A hypothesis is an educated guess, based an educated guess, based

on observation.on observation. Usually, a hypothesis can be supported or Usually, a hypothesis can be supported or

refutedrefuted through experimentation or more through experimentation or more observation. A hypothesis can be observation. A hypothesis can be disproveddisproved, but not , but not provenproven to be true. to be true.

Example of HypothesisExample of Hypothesis If you see no difference in the cleaning ability of If you see no difference in the cleaning ability of various laundry detergents, you might hypothesize various laundry detergents, you might hypothesize that cleaning effectiveness is not changed by which that cleaning effectiveness is not changed by which detergent you use. detergent you use.

You can see this hypothesis can be disproved if a You can see this hypothesis can be disproved if a stain is removed by one detergent and not another.stain is removed by one detergent and not another.

On the other hand, you cannot prove the hypothesis. On the other hand, you cannot prove the hypothesis. Even if you never see a difference in cleanliness of Even if you never see a difference in cleanliness of your clothes after trying a thousand detergents, there your clothes after trying a thousand detergents, there might be one out there you haven’t tried that could might be one out there you haven’t tried that could make a difference.make a difference.

TheoryTheory A scientific theory summarizes a A scientific theory summarizes a hypothesishypothesis or group of or group of hypotheseshypotheses that that have been supported with repeated have been supported with repeated testing. testing.

A theory is valid as long as A theory is valid as long as there is no there is no evidence against it.evidence against it. Therefore, theories Therefore, theories can be disproved.can be disproved.

Basically, if evidence accumulates to Basically, if evidence accumulates to support a hypothesis, then the hypothesis support a hypothesis, then the hypothesis can become can become acceptedaccepted as a good as a good explanation of why something happens.explanation of why something happens.

Example of TheoryExample of Theory The universe began as an infinitesimally small The universe began as an infinitesimally small and dense item from which exploded space and and dense item from which exploded space and time. time.

Scientists have accumulated evidence such as Scientists have accumulated evidence such as the red shift, background radiation, and the the red shift, background radiation, and the presence of lighter elements such as hydrogen presence of lighter elements such as hydrogen and helium to help support this theory.and helium to help support this theory.

We could eventually find a piece of information We could eventually find a piece of information that would disprove this theory, but we could that would disprove this theory, but we could never prove it completely…there could always never prove it completely…there could always be information out there we haven’t found yet be information out there we haven’t found yet that disproves it.that disproves it.

LawLaw A law generalizes a body of A law generalizes a body of observationsobservations.. At the time it is made, no exceptions have At the time it is made, no exceptions have

been found to a law. been found to a law. Scientific laws explain things, but they do Scientific laws explain things, but they do

not not describe themdescribe them.. One way to tell a law and a theory apart is One way to tell a law and a theory apart is

to to ask if the description gives you a ask if the description gives you a means to explain ‘why’.means to explain ‘why’. If it If it doesdoes, it’s a , it’s a theorytheory. If it does . If it does notnot, it’s a , it’s a lawlaw..

Example of LawExample of Law

Consider Newton’s Law of Gravity. Consider Newton’s Law of Gravity. Newton could use the law to predict the Newton could use the law to predict the behavior of a dropped object, but he behavior of a dropped object, but he couldn’t explain why it happened. couldn’t explain why it happened.

So in summary…So in summary… ……there is no ‘there is no ‘proofproof’ or ‘absolute ’ or ‘absolute truthtruth’ in science. The ’ in science. The

closest we get are facts, which are indisputable closest we get are facts, which are indisputable observationsobservations. .

Still, wording and definitions matter. If you define Still, wording and definitions matter. If you define proofproof as arriving at a logical conclusion, based on the as arriving at a logical conclusion, based on the evidence, then there is evidence, then there is proofproof in science. in science.

We work under the definition that to prove We work under the definition that to prove something implies it can never be something implies it can never be wrongwrong, which , which is different.is different.

If you’re asked to define hypothesis, theory, or If you’re asked to define hypothesis, theory, or lawlaw, , keep in mind the definitions of proof and these words keep in mind the definitions of proof and these words can vary depending on the scientific can vary depending on the scientific disciplinediscipline. .

What is important is to realize they don’t all mean the What is important is to realize they don’t all mean the same thing, and same thing, and they cannot be they cannot be used used interchangeablyinterchangeably..

Let’s Practice!Let’s Practice! 1. Species change over time due to heavy 1. Species change over time due to heavy

competition among individuals so that those competition among individuals so that those best suited for an environment survive and best suited for an environment survive and reproduce.reproduce.

TheoryTheory 2. The amount of force needed to move an 2. The amount of force needed to move an

object is proportional to its mass and object is proportional to its mass and acceleration.acceleration.

LawLaw 3. An object in motion will remain in motion 3. An object in motion will remain in motion

unless acted on by an unbalanced force.unless acted on by an unbalanced force. LawLaw

Time for a WS!Time for a WS!

Theory or Law? WSTheory or Law? WS