Chemistry and Physics Review Steven Nixon

Table of contents Periodic Table of the Elements Density Viscosity Chemical and Physical Changes Law of conservation of mass pH Scale Solute and Solvent Like dissolves like Things to remember Newton's 3 laws Waves Polarization Reflection and Refraction Resonance Law of conservation of energy Conduction, Convection, Radiation Conduction, Convection, Radiation Fossil Fuels and Alternative Renewable Fossil Fuels and Alternative Renewable Chemistry information 2

Periodic Table of the Elements 3

Density Density=mass(g) Volume(ml or cm3). Density of water is 1 g/ml. If the density of a substance is less than 1 it will float. If the density of a substance is greater then 1 it will sink. 4

Viscosity Viscosity is a fluids resistance to flow. Ex. Honey, Molasses, and Ketchup If you increase the temp you decrease the viscosity.(Pou rs quicker) If you decrease the temp you increase the viscosity.(Pou rs Slower) Buoyancy-An upward force exerted by a fluid. 5

Chemical and Physical Changes Physical change- No new substances are formed. Crushing, grinding, dissolving. Ex. All phase changes are physical changes. Ex. Liquid to solid- Freezing. Solid to Liquid- Melting, Solid to gas-Sublimation, Liquid to gas- evaporating. Chemical Change- New substances are formed. Ex. Burning, Rustin, Tarnishing. 6

Law of conservation of mass Law of conservation of mass-matter cannot be created or destroyed in a chemical reaction. Reactants Na + CI Product NaCI Unbalanced 2Na + CI NaCI Balanced 7

Law of conservation of mass You can only add coefficients when balancing never chance subscripts. Same for mass 2Na + CI NaCI 2g + 1g = 3g Total mass of the reactants must equal total mass of the products. 8

Water Molecule Water is a polar molecule. It has a slightly negative end(oxygen end) and a slightly positive end (Hydrogen end.) Because water is polar it tends to dissolve other polar compounds. Water expands when it freezes which provides an insulating layer for fish in lakes and pounds. 9

pH Scale Substances that can conduct an electric current when they are dissolved in water are electrolytes. Strong Acids and Strong bases are electrolytes as well as NaCl 10

Solute and Solvent To increase the rate at which a solid(Solute) dissolves in a liquid(Solvent). Increase Temperature. Increase the surface area. Stir To increase the rate at which a gas(solute) dissolves in a liquid(Solvent). 1.Decrease temperature. 2. Increase pressure. 11

Like dissolves like Polar dissolves Polar Water sugar Non-Polar dissolves no polar Paint thinner Oil-based paint 12

Things to remember Speed(m/s) and velocity(m/s) are calculated in the same way. Velocity just includes direction. Acceleration (m/s 2 ) is speeding up, slowing down or changing directions. Work (J) is when force applied to the object is the same as the direction in which the object moves. If the object does not move it is not work. 13

Newton's 3 laws 1 st law: Any object in motion will stay in motion, and any object at rest will stay at rest, until it is acted on by an unbalanced force.(ex. Friction or gravity). This law is also referred to as the law of inertia. 2 nd Law: F(N)=mass x Acceleration Remember acceleration due to gravity is 9.8 m/s 2 as is located on the formula chart in the box below. 3 rd Law: For every action there is a equal and opposite reaction. 14

Waves 15

Polarization A polarizing filter is made up of long molecules arranged parallel to one another. Between the molecules are narrow slits. The only light that passes through a polarizing filter is light that vibrates parallel to the filters slits. The light that passes through a polarized light. Polarized light vibrated in only a single direction, such as a horizontal plane. 16

Reflection and Refraction Reflection- Wave strikes and object and bounces back. Refraction- Wave bends due to a change in its speed. Ex: Going from air into water or air into glass. Lenses refract light. 17

Resonance Resonance– The natural frequency at which an object vibrates. Ex: A tuning fork with a frequency of 256 Hz vibrates when struck. Because of these vibrations, a nearby tuning fork begins to vibrate without being struck. 18

Law of conservation of energy Law of conservation of energy: Energy is never created nor destroyed. Conserve means to save Energy can be converted to other forms of energy. Example: When gasoline is burned in a cars engine, for Instance, chemical energy stored in the gasoline is converted to other forms. Only some of this energy is used to move the car forward. Much of the rest is wasted as heat. 19

Conduction, Convection, Radiation Conduction-Transfer of heat by direct contact.(Solids) Convection- Transfer of heat by the movement of a current(Convection Current)(Liquids and gases transfer heat by this method because their fluid motion) Radiation-Transfer of heat by means of electromagnetic waves.(Sun and you can also feel radiation by sitting near a fire in a fireplace) 20

Fossil Fuels and Alternative Renewable Fossil Fuels-(Nonrenewable) coal, natural gas, oil. Alternative Renewable-Solar(sun), Wind, Hydro(water), Geothermal(Geysers) 21 Fossil Fuels Alternative Renewable

Chemistry information mpounds/Molecules_Compounds.htm mpounds/Molecules_Compounds.htm 22