Matter Chapter 2 Pages 58-81

Matter Anything that has mass and takes up space

States of matter The three states of matter are solids, liquids and gasses.

Characteristic Properties Regardless of state of matter, a substance has a unique characteristic property.

Elements Cant be broken down into another substance.

ELEMENTS

Compound Chemical Combination of elements. EX: H 2 0 water CO 2 Carbon Dioxide C H 11 Sugar C 6 H 12 O 6 Glucose

Atom The smallest particle of an element.

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Molecule A group of atoms joined together. chocolate

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Chemical Bond The force that holds the atoms together.

Formula Ratio of atoms of each element in a compound. Theobromine, C 7 H 8 O 4 N 2 or Chocolate

Law of Conservation of Matter Matter is neither created nor destroyed during a chemical change. It recombines to make a new type of chemical.

Pure Substance One kind of matter with no substances mixed in. EX. Sugar, gold, silver, salt.

Mixture When two or more substances are mixed together but have different properties. EX: Salt Water

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Solution As well mixed as possible or when a substance has dissolved.

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Changes in Matter Physical Change: When the state of matter changes.

Physical Change whipping egg whites (air is forced into the fluid, but no new substance is produced) magnetizing a compass needle (there is realignment of groups ("domains") of iron atoms, but no real change within the iron atoms themselves). boiling water (water molecules are forced away from each other when the liquid changes to vapor, but the molecules are still H2O.) dissolving sugar in water (sugar molecules are dispersed within the water, but the individual sugar molecules are unchanged.) dicing potatoes (cutting usually separates molecules without changing them.)

Changes in Matter cont… Chemical Change: When a substance(s) combine or decompose into a new substance.

Examples of a chemical change iron rusting (iron oxide forms) gasoline burning (water vapor and carbon dioxide form) eggs cooking (fluid protein molecules uncoil and crosslink to form a network) bread rising (yeast converts carbohydrates into carbon dioxide gas) milk souring (sour-tasting lactic acid is produced) suntanning (vitamin D and melanin is produced)

Type of characteristic properties Boiling Points: The temperature at which a liquid boils. Water's boiling point is 100 °C

Melting/Freezing Points Temperature at which a solid turns into a liquid.

Intermolecular forces (IMFs): These are forces that hold particles (molecules) together.

Energy and State Change When a substance changes state: Solid liquid gas = gaining energy Gas liquid solid = loses energy

Temperature affects state. Substances with weak IMFs become liquids and gasses at low temperatures. In contrast, substances with strong IMFs can stay in a solid state even at extreme temperatures. Substances with strong IMFs become liquids and gasses at high temperatures.