Why do we have them?Why do we have them?

When we measure things, we want to measure to the place we are sure of and guess one more space.

So, they show the So, they show the uncertaintyuncertainty in in our measurementsour measurements

Since the marks on this Since the marks on this ruler are subdivided as ruler are subdivided as they are, our answer for they are, our answer for the length of this nail has the length of this nail has

33 significant figures. significant figures.

However, we only However, we only have significant figures have significant figures

when we are when we are measuringmeasuring something. something. CountingCounting will give you will give you

an exact number.an exact number.

Lab EquipmentLab Equipment

BeakerBeaker

Holds chemicalsHolds chemicals during mixing, during mixing, heating, and heating, and storagestorage

Acts like a bowlActs like a bowl InaccurateInaccurate

measuring devicemeasuring device

Erlenmeyer FlaskErlenmeyer Flask

Holds chemicalsHolds chemicals during mixing, during mixing, heating, and heating, and storagestorage

Acts like a bowlActs like a bowl InaccurateInaccurate

measuring devicemeasuring device

Volumetric FlaskVolumetric Flask

Holds chemicalsHolds chemicals during mixing and during mixing and storagestorage

Accurate Accurate measurement of a measurement of a specific volumespecific volume

FunnelFunnel

Aids in pouring and Aids in pouring and filtering processfiltering process

Watch GlassWatch Glass

Acts as a cover Acts as a cover during heating and during heating and storagestorage

Looks like a giant Looks like a giant contact lensecontact lense

Evaporating DishEvaporating Dish

Container used to Container used to allow materials to allow materials to evaporateevaporate

Crucible and CoverCrucible and Cover

Used to hold Used to hold materials that need materials that need to be heated to to be heated to higher higher temperaturestemperatures

Crucible TongsCrucible Tongs

Used to hold Used to hold heated cruciblesheated crucibles

Bunsen BurnerBunsen Burner

Used to heat Used to heat materialsmaterials

StrikerStriker

Used to light Used to light burnersburners

BalanceBalance

Used to determine Used to determine the mass of the mass of materialsmaterials

Graduated CylinderGraduated Cylinder

Used to measure Used to measure liquids accuratelyliquids accurately

Must look at Must look at meniscus of the meniscus of the liquid when taking liquid when taking readings readings

Iron RingIron Ring

Attaches to ring Attaches to ring standstand

Holds various Holds various equipment while equipment while they are heated they are heated

Buret ClampBuret Clamp

Attaches to ring Attaches to ring standstand

Holds burets during Holds burets during titrations titrations

Utility ClampUtility Clamp

Attaches to ring Attaches to ring standstand

Holds various thin Holds various thin equipment while equipment while they are heated they are heated

GogglesGoggles

Protect eyes during Protect eyes during experimentsexperiments

Ring StandRing Stand

Used to support Used to support devices during devices during laboratory laboratory proceduresprocedures

BuretBuret

Used to accurately Used to accurately and slowly add and slowly add liquidsliquids

Used most often in Used most often in titration titration experimentsexperiments

ThermometerThermometer

Used to measure Used to measure the temperature of the temperature of various materialsvarious materials

Gas-collecting tubeGas-collecting tube

Tube used to Tube used to collect gases.collect gases.

Usually used in the Usually used in the inverted positioninverted position

Test TubeTest Tube

Used to hold small Used to hold small samples during samples during heating and heating and storagestorage

Test Tube RackTest Tube Rack

Used to hold Used to hold multiple test tubesmultiple test tubes

Test Tube HolderTest Tube Holder

Used to hold one Used to hold one test tube, usually test tube, usually during heating or during heating or transporting test transporting test tubetube

ForcepsForceps

Used to pick up Used to pick up and separate small and separate small solidssolids

SpatulaSpatula

Used to scoop Used to scoop small quantities of small quantities of solidssolids

Can be used to Can be used to scrape the inside of scrape the inside of various equipmentvarious equipment

Mortar and PestleMortar and Pestle

Used to crush and Used to crush and grind materialsgrind materials

PipetPipet

Used to dispense Used to dispense small quantities of small quantities of liquidsliquids

StoppersStoppers

Come in various Come in various sizessizes

Used to block Used to block openings of various openings of various equipmentequipment