Section 1 – Classifying Matter Previously, we watched a 30 minute video on “Properties of matter” Key Questions 1] 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?
TN Standards CLE – Evaluate pure substances and mixtures
Matter Bellwork A – Which of the following is not an example of matter : – ( sunglasses, beach towel, sunlight, water ) Bellwork B – Elements, Compounds, and Mixtures are all ____________ ?
Matter Matter – Anything that has mass and takes up space Matter is either an element, compound, molecule, or mixture Element – a substance that cannot be broken down into simpler substances by chemical means Compounds – substance made of atoms from different elements BONDED TOGETHER
More on Matter Molecule – smallest unit of a substance that behaves like the substance – Not always the same as a compound!! – Atoms combined but can be same element – Compounds are molecules; molecules not always compounds Examples of substances that exist in molecule form, BUT ARE NOT COMPOUNDS: – Oxygen and Nitrogen gas in Air – Hydrogen and Chlorine gas – Phosphorus If a compound: each molecule of that compound will have two or more chemically combined ( BONDED ) elements
More on Matter Compounds have unique properties – Table salt, water, sugar, gasoline Molecules have their own chemical formulas – H 2 O, CO 2, H 2, HF
Atoms What about Atoms – are ( DO ) they matter? Yes! Atoms – smallest unit of an element that maintains the chemical properties of that element Atoms that make up a molecule act as a unit – Again, this can be a compound or only a molecule
Pure Substances & Mixtures Pure Substance – matter with definite composition ( or concentration of the components ) – Elements, compounds, and molecules Mixtures – combination of substances NOT chemically combined – Heterogenous and Homogeneous
Pure Substances and Mixtures What is the difference? – Chemical bonds ( mixtures are not chemically bonded ) Example of pure substance? – Water, carbon dioxide Example of homogeneous mixture? – Salt or sugar water ( dissolved ), vinegar Example of heterogenous mixture? – Pulpy orange juice, skittles, salad
Mixtures - Defined Homogeneous – looks the same throughout Heterogenous – does not look the same throughout
Concept Map Word List: Matter, Pure Substances, Atoms?, Elements, Compounds, Mixtures, Homogeneous, Heterogeneous,
Bellwork What are the two different types of mixtures?
Bellwork What are the two different types of mixtures? Homogeneous and Heterogeneous
Section 2/3 – Properties & Changes of Matter Key Questions 1] 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?
TN Standards CLE – Explore matter in terms of its physical and chemical properties CLE – Investigate chemical and physical changes
Physical Properties Physical properties are characteristics observed without changing the identity of the substance Examples: color, texture, density, melting temperature, boiling temperature Physical properties help determine many uses
Chemical Properties Chemical properties are characteristics observed only by changing the identity of the substance Examples: flammability, reactivity
Changes Physical changes do not change the identity of the substance – Cutting hair, Cutting paper – Can be reversed Chemical changes do – Burning, Rusting, Color, Smell – Can’t be reversed