Chemistry Notes: Particle Theory, Properties, and Groups

Particle Theory of Matter: - All matter is made up of tiny particles. - All particles of a pure substance are identical and unique. - Particles are always moving. - Particles attract each other. - Particles at a higher temperature move faster. ### Physical Properties: - Colour - Texture - Odour - Clarity - Luster (shiny, dull) - Taste - State (solid, liquid, gas) - Hardness (ability to be scratched) - Malleability (ability to be bent into different shapes) - Ductility (ability to be pulled into long, thin wires) - Melting and boiling points - Solubility (ability to dissolve) - Viscosity (how easily it flows) - Density #### Example: - $Ca<em>3(PO</em>4)_2$ - Ca - 3 - P - 2 - O - 8 ### Chemical Properties: - Combustibility (ability to burn) - Reactivity - Sensitivity to light ### Formula for Density: - $D = \frac{m}{V}$, $m = D \cdot V$, $V = \frac{m}{D}$- D = density - m = mass - V = volume - The density of water is 1g/cm³ or 1g/ml. ### Groups in the Periodic Table: #### Group 1: Alkali Metals - Solid, shiny metals. - Extremely reactive. - React with water to produce hydrogen gas. - Found in nature as compounds. #### Group 2: Alkaline Earth Metals - Solid, metal, more dense than alkali metals. - Very reactive. - Corrosive. - Found in nature as compounds. #### Group 7: Halogens - Non-metals; can be yellow, green gases; a red-brown liquid; or violet/black solids. - Extremely reactive. - Found in