1Chapter 2 - Matter Section 1 – Classifying Matter Section 2 – Properties of MatterSection 3 – Changes of Matter
2Section 1 – Classifying Matter Previously, we watched a 30 minute video on “Properties of matter”Key Questions1] How can matter be classified?2] Why are carbon and copper classified as elements?3] How are elements related to compounds?4] What is the difference between a pure substance and a mixture?
3TN StandardsCLE – Evaluate pure substances and mixtures
4MatterBellwork A – Which of the following is not an example of matter :( sunglasses, beach towel, sunlight, water )Bellwork B – Elements, Compounds, and Mixtures are all ____________ ?
5Matter Matter – Anything that has mass and takes up space Matter is either an element, compound, molecule, or mixtureElement – a substance that cannot be broken down into simpler substances by chemical meansCompounds – substance made of atoms from different elements BONDED TOGETHER
6More on MatterMolecule – smallest unit of a substance that behaves like the substanceNot always the same as a compound!!Atoms combined but can be same elementCompounds are molecules; molecules not always compoundsExamples of substances that exist in molecule form, BUT ARE NOT COMPOUNDS:Oxygen and Nitrogen gas in AirHydrogen and Chlorine gasPhosphorusIf a compound: each molecule of that compound will have two or more chemically combined ( BONDED ) elements
7More on Matter Compounds have unique properties Table salt, water, sugar, gasolineMolecules have their own chemical formulasH2O, CO2, H2, HF
8Atoms What about Atoms – are ( DO ) they matter? Yes! Atoms – smallest unit of an element that maintains the chemical properties of that elementAtoms that make up a molecule act as a unitAgain, this can be a compound or only a molecule
9Pure Substances & Mixtures Pure Substance – matter with definite composition ( or concentration of the components )Elements, compounds, and moleculesMixtures – combination of substances NOT chemically combinedHeterogenous and Homogeneous
10Pure Substances and Mixtures What is the difference?Chemical bonds ( mixtures are not chemically bonded )Example of pure substance?Water, carbon dioxideExample of homogeneous mixture?Salt or sugar water ( dissolved ), vinegarExample of heterogenous mixture?Pulpy orange juice, skittles, salad
11Mixtures - Defined Homogeneous – looks the same throughout Heterogenous – does not look the same throughout
13BellworkWhat are the two different types of mixtures?
14Bellwork What are the two different types of mixtures? Homogeneous and Heterogeneous
15Section 2/3 – Properties & Changes of Matter Key Questions1] Why are color, volume, and density classified as physical properties?2] Why are flammability and reactivity classified as chemical properties?3] Why is getting a haircut an example of a physical change?4] Why is baking bread an example of a chemical change?5] How can mixtures and compounds be broken down?
16TN StandardsCLE – Explore matter in terms of its physical and chemical propertiesCLE – Investigate chemical and physical changes
17Physical PropertiesPhysical properties are characteristics observed without changing the identity of the substanceExamples: color, texture, density, melting temperature, boiling temperaturePhysical properties help determine many uses
18Chemical PropertiesChemical properties are characteristics observed only by changing the identity of the substanceExamples: flammability, reactivity
19Changes Physical changes do not change the identity of the substance Cutting hair, Cutting paperCan be reversedChemical changes doBurning, Rusting, Color, SmellCan’t be reversed