Warm UpWarm Up 8-8-25-1525-15

1. Convert 30 in to ft1. Convert 30 in to ft

2. Convert 19 g to kg2. Convert 19 g to kg

3. Convert 7.4 m to cm3. Convert 7.4 m to cm

4. Which is larger: 658 cm or 658 km?4. Which is larger: 658 cm or 658 km?

AgendaTurn in Lab VolumeGo over Safety QuizNotes Unit 1-3Lab Density

HomeworkQuiz Unit 1Aug 28 - Online HW Unit 1Sept 3 - Test Unit 1

Unit 1-3How is Matter Classified?

What does it mean to classify What does it mean to classify information?information?

Why is it important to classify Why is it important to classify information?information?

Pure SubstancesPure Substances

Pure substancePure substance One type of element or a single One type of element or a single

compound, that has definite chemical compound, that has definite chemical and physical propertiesand physical properties

– Examples include copper, oxygen, and Examples include copper, oxygen, and carbon dioxidecarbon dioxide

– Elements, molecules or compoundsElements, molecules or compounds

Pure SubstancesPure Substances

Elements Elements Pure substances that contain only Pure substances that contain only

one type of atom (e.g. He, Li)one type of atom (e.g. He, Li)

– Some elements are Some elements are diatomicdiatomic (they are (they are never found naturally by themselves. never found naturally by themselves. They have a “buddy”)They have a “buddy”) HH22, O, O22, N, N22, Cl, Cl22, Br, Br22, I, I22, F, F22

Pure SubstancesPure Substances MoleculesMolecules

two or more atoms (usually the same two or more atoms (usually the same elements)elements)

Diatomic gasses (HDiatomic gasses (H22, O, O22, N, N22, Cl, Cl22, Br, Br22, I, I22, F, F22))

– A molecule is the smallest unit of a substance that A molecule is the smallest unit of a substance that keeps all the physical and chemical properties of keeps all the physical and chemical properties of that substancethat substance

– It can consist of one atom or two or more atoms It can consist of one atom or two or more atoms bonded togetherbonded together

– Example: Helium versus HydrogenExample: Helium versus Hydrogen

Pure SubstancesPure Substances

CompoundsCompounds A substance made up of atoms of A substance made up of atoms of

two or more two or more differentdifferent elementselements joined by chemical bonds (e.g. COjoined by chemical bonds (e.g. CO2)

All compounds are molecules

– Compounds can be made from their Compounds can be made from their elements and also broken down into elements and also broken down into their componentstheir components

Pure SubstancesPure Substances

Element Molecule

Compound or Molecule Mixture

MixturesMixtures MixtureMixture: A combination of two or : A combination of two or

more substances that are more substances that are NOT NOT chemically combinedchemically combined

– Example: air is a mixture of nitrogen, Example: air is a mixture of nitrogen, oxygen, argon, and carbon dioxideoxygen, argon, and carbon dioxide

– Example: pure water is NOT a mixture Example: pure water is NOT a mixture because H is chemically bonded to O to because H is chemically bonded to O to form Hform H22OO

MixturesMixtures Homogeneous mixturesHomogeneous mixtures

When pure substances are When pure substances are distributed evenly throughout the distributed evenly throughout the mixturemixture

– The different components of the mixture The different components of the mixture cannot be identified by looking at itcannot be identified by looking at it

– Examples: air, gasoline, syrupExamples: air, gasoline, syrup

MixturesMixtures Heterogeneous mixturesHeterogeneous mixtures

When pure substances are NOT evenly When pure substances are NOT evenly distributed throughout the mixturedistributed throughout the mixture

– You can see the different You can see the different

components in the mixturecomponents in the mixture– Example: ice tea, cerealExample: ice tea, cereal

Properties of MatterProperties of Matter Chemical Properties: Chemical Properties: A property A property

of matter that let it react with of matter that let it react with another chemicalanother chemical

– Chemical properties can only be Chemical properties can only be identified by trying to cause a chemical identified by trying to cause a chemical changechange

Properties of MatterProperties of Matter

Physical Property: Physical Property: A property that A property that can be determined without can be determined without changing the nature of the changing the nature of the substancesubstance– Example: sugar’s physical properties would Example: sugar’s physical properties would

include that it is solid, whiteinclude that it is solid, white– More examples:More examples:

State of matterState of matter Melting pointsMelting points Boiling point Boiling point Mass and volumeMass and volume

Properties of MatterProperties of Matter

Density = mass/volumeDensity = mass/volume g/cmg/cm33

The density of an object is the The density of an object is the same no matter its volume same no matter its volume

-Density is also a physical property of -Density is also a physical property of matter that can be used to identify matter that can be used to identify substances (stuff per space)substances (stuff per space)

Density Example Density Example ProblemsProblems

1. What is the density of an object that 1. What is the density of an object that weights 2200g and has a volume of 100cmweights 2200g and has a volume of 100cm33??

2. Gold’s density is 19.3g/cm2. Gold’s density is 19.3g/cm33 If a gold bar If a gold bar has mass of 150g what is its volume?has mass of 150g what is its volume?

3. Find the density of this cube.3. Find the density of this cube.

Mass = 30g Mass = 30g

Density LabDensity Lab Follow the lab procedure to find the Follow the lab procedure to find the

volume of pennies and metal cylindersvolume of pennies and metal cylinders Find the unknown materials used to Find the unknown materials used to

make the cubes by finding its densitymake the cubes by finding its density Lab due before class is overLab due before class is over

Unit 1 Density WS Unit 1 Density WS due at the end of due at the end of next classnext class

Mixture Vs. Compound Mixture Vs. Compound ReviewReview

A mixture is A mixture is composed of two or composed of two or more substances that more substances that are physically mixedare physically mixed

Properties of Properties of mixtures reflect the mixtures reflect the substances it substances it containscontains

Mixtures can have Mixtures can have varying proportionsvarying proportions

Mixtures can be Mixtures can be separated based on separated based on the physical the physical properties of the properties of the substancessubstances

A compound is A compound is composed of two or composed of two or more elements more elements chemically joinedchemically joined

Properties of Properties of compounds have compounds have different properties different properties than the elements that than the elements that make them upmake them up

Compounds have Compounds have definite proportionsdefinite proportions

Compounds can only Compounds can only be separated into its be separated into its components through components through chemical changechemical change