Matter

1. Matter Materials which always have the same composition

2. Two Types • Elements • Substance composed of only one kind of atom • (1-118 in the periodic table) • Compound • Substance composed of more than one kind of atom: CO2, H2O, H2SO4, C6H12O6

3. Properties of Matter • General properties: • Properties that all substances have • Weight, length, mass, volume • Physical properties • Depend on the substance themselves • Color, temperature, malleability, ductility, conductivity, smell, crystalline shape, melting point, boiling point, freezing point, and density. • Two Types • Extensive property: • Physical property that can change after a physical change has occurred • Example: tear a piece of paper it is now half its size • Intensive property: • Physical property that will not change after a physical change has occurred. • Example tear a piece of paper it is still paper

4. Physical Properties of Matter • Malleability: • The ability of a substance to be hammered into shape. • Ductilityor ductile: • The ability to be drawn into a wire. • Conductivity: • The ability of a substance to produce heat or electricity. • Crystalline shape: • Form taken up by the substance. • Boiling point • Temperature at which the substance enters its gaseous state. • Melting point: • Temperature at which the substance enters its liquid state. • Elasticity: • a physical property of materials which return to their original shape after the stress that caused their deformation is no longer applied.

5. Freezing point: • Temperture at which the substance enters its solid state • Luster: • How shinny an object is • Hardness: • The ability of one object to scratch another • Solubility: • The ability of one substance to be stirred into another substance • Density: • mass per given volume • Units: g/cm3 • Mass • How much space matter takes up • Volume • Space taken up by a liquid usually expressed in ml or cm3

6. Viscosity: • A measurement of how resistant a liquid is to flow and usually becomes greater as temperatures decrease • How thick something is • Reactivity: • How one substance reacts to another

7. Solutions • Contain two parts: • Solute: • The part being dissolved • Solvent: • The part doing the dissolving • Example: • Sugar + Water • Solute is • sugar • Solvent is: • water

8. Chemical Properties • Depend on the action of the substance in the presence of other substances • Examples: • Does it burn? • Does it help other things to burn? • Does it react with water? • Does it react with acids/bases?

9. Changes of Matter • Physical change: • Change in which no new material is made • Change cannot be reversed • Example: Broken Mirror • Chemical Change • Change in which new material is made • Change cannot be reversed • Example • Wood + Fire ashes

10. Physical States of Matter • Solid: • Has no definite shape • Crystalline solid: • Arranged in definite pattern. Examples: cubes of sugar or salt • Amorphous solid: • Solid that transitions between a liquid and a solid phase. Example: cornstarch and water or silly putty • Liquid: • Has a definite shape but no definite volume. • It takes the shape of its container. • Gas: • Has no definite shape or volume. • Diffuse throughout its container. • Molecules move extremely fast and a container cannot hold them • Phase Change: • When a substance changes from one state to another • Solid  Liquid  Gas • Ice  water  water vapor

11. Condensation: • is the change of the physical state of matter from gaseous phase into liquid phase • Vaporization: • The change of the physical state of matter form the liquid phase to the gaseous phase • Two Kinds: • Evaporation: • is a phase transition from the liquid phase to gas phase that occurs at temperatures below the boiling temperature at a given pressure. Evaporation usually occurs on the surface. • Boiling: • is a phase transition from the liquid phase to gas phase that occurs at or above the boiling temperature. Boiling, as opposed to evaporation, occurs below the surface. • Sublimation: • When solids go directly from a solid to a gas skipping the liquid state. • Example: dry ice

12. Endothermic vs. Exothermic Chemical Reactions • Exothermic reactions • Is a chemical reaction that releases energy in the form of light or heat • These reactions will generally feel hot • Endothermic reactions • Is a chemical reaction in which heat is absorbed from its environment • These reactions will generally feel cold

13. Mixtures of Matter • Heterogeneous: • A mixture that doesn’t blend smoothly throughout • Example: sand, fruit salad, pizza • Homogeneous: • Has constant composition or blends smoothly throughout • Example: apple juice, shaving crème • Note: Solutions are homogenous mixtures that have a smooth composition throughout • Example: water, Kool-aid

14. Separating Mixtures • Filtration: • Separating heterogeneous mixtures composed of solids and liquids; by using filter paper and funnel. • Distillation: • Homogenous mixtures can be separated by this method; based on the different boiling points of the substances involved • Crystallization: • A separation technique resulting in the formation of pure solid crystals or particles from a solution containing dissolved substances. • Example: making rock candy from a sugar solution • Chromatography: • A technique separating the components of a mixture on the basis of the tendency of each to travel across the surface of another material • Example: separating ink as it travels across paper- because the components of the ink spread through the paper at different rates because each has a different molecular formula and molecular mass. The substances having the heaviest molecular mass travel slower and separate out last.

15. Pneumatic • The use of compressed air to generate power • Hydraulics: • hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids.