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Anything that has mass and occupies space.
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Anything that has mass and occupies space TOPIC: Properties of MatterDo Now:1) Define Matter: 2)A sample of CO2(s) and a sample of CO2(g) different in their 1) chemical composition 2) empirical formula 3) molecular structure 4) physical properties
Physical Properties • Describe the appearance and form of matter Words: • color, texture, luster, odor, solid, • liquid, gas Measurements: • a number and a unit
From the do now…solid vs gas physical properties • A sample of CO2(s) and a sample of CO2(g) different in their 1) chemical composition 2) empirical formula 3) molecular structure 4) physical properties
Other physical properties include Density, boiling point (BP), and melting point (MP) (where can you find the density of Al? Fe?) Solubility in water (g/ml) (how well it dissolves in water) Intensive Properties: sample size DOES NOT matter
Other physical properties like volume and mass depend on sample size Extensive Properties: sample size matters
Chemical Properties • Describe how matter behaves in presence of other matter • Describe how matter changes intoanother kind of matter • Flammable • Corrosive • Ability to neutralize acids or bases
Physical or Chemical? - physical • Reddish brown • Forms new substances with HNO3 • MP = 1085C • Density = 8.92 g/cm3 • Reacts to form green copper carbonate • Shiny • Malleable • BP = 2570C - chemical - physical - physical - chemical - physical - physical - physical
Physical Change • The form or appearance of sample may change but identity remains same • Cutting, crushing, grinding, tearing
Dissolving is physical change • Think of sugar in water • still have sugar – you just spread it out with water molecules in between • C6H12O6(s) C6H12O6(aq) Aq = dissolved in water
Phase changes are physical changes • No new substance is created (chemical formula stays the same) • Ex: • ice melting: H2O(s) H2O(l) • water boiling: H2O (l) H2O(g)
Chemical Change • chemical change - identity of matter is changed • new substance with unique properties is formed • The chemical formula changes • Ex: 2H2O(l) 2H2(g) + O2(g)
Burning • Common name for oxidation reaction • Burning means reacting with oxygen • Burning is chemical change, because original substance is changed into new kinds of matter Ex: CH4(g) + 2O2(g) CO2(g) + 2H2O(g)
Evidence of Chemical a Chemical Change • Bubbles (formation of a gas) • Color change • Heat • Light • Formation of a precipitate (new substance)