Physical Science Fact Sheet 1 – SOLs 2-4

SOL 2: Classification of Matter

· All matter is made of particles called atoms.

· An element is a pure substance made of 1 type of atom that cannot be broken down further.

· A compound is a pure substance made of more than 1 type of atom chemically combined.

· Organic compounds have C and H.

· A mixture is made of more than one substance physically combined and can be separated.

· Physical Properties are observed or measured without changing the identity of the substance.

· Example Physical Properties: Mass, Volume, Melting point, Boiling point, Luster (Shininess), Malleability (Bendable), Conductivity, Density (Mass/Volume), Solubility (Dissolving), and any other properties detected by your 5 senses.

· Chemical Properties make a new substance when measured.

· Example Chemical Properties: Combustibility (Burning), Rust, Tarnish, Reactivity, Acidity, Basicity, and pH.

SOL 4: Periodic Table

· Periodic table is arranged according to atomic number or protons.

· The 7 Periods run horizontal (side to side) and determine the number of electron shells an atom has.

· 1st: Up to 2 electrons

· 2nd: Up to 8 electrons

· 3rd: Up to 18 electrons

· The 18 Groups or Families run vertical (up and down) and determine the chemical behavior or reactivity of elements.

· Elements in the same group or family have the same number of valence, outside electrons involved in reactions or bonds.

· Family 1: 1 Valence, lose 1 to reach stability.

· Family 2: 2 Valence, lose 2 to reach stability.

· Family 13: 3 Valence, lose 3 to reach stability.

· Family 14: 4 Valence, gain/lose 4 to reach stability.

· Family 15: 5 Valence, gain 3 to reach stability.

· Family 16: 6 Valence, gain 2 to reach stability.

· Family 17: 7 Valence, gain 1 to reach stability.

· Family 18: 8 Valence, already stable. No changes.

· Metals: shiny (luster), malleable, conductive elements found to the left of the staircase on the table (except H).

· Alkali Metals are the most reactive metals. (Family 1)

· Nonmetals: dull, brittle, rigid, poorly conductive elements found to the right of the staircase on the table (including H).

· Halogens are the most reactive nonmetals. (Family 17)

· Noble Gases are the non-reactive elements. (Family 18)

· Metalloids: share properties of both metals and nonmetals, and found between the two on the periodic table’s staircase.

· Ionic Bond: a transfer of electrons from a metal to a nonmetal.

· Covalent Bond: a sharing of electrons between two nonmetals.

SOL 3: Atomic Theory

· Earliest -- Dalton – All matter is made of atoms that cannot be created or destroyed. All atoms for an element are identical. Billiard Ball Model

· Thomson – Atoms are positive spheres with negative electrons embedded throughout it. Plum Pudding Model.

· Rutherford – Atoms have a dense positive core made of protons called the nucleus. The electrons are separate and far to the outside of the nucleus. Nuclear Model.

· Chadwick – Discovered that the nucleus contains uncharged particles called neutrons.

· Bohr – An atom’s electrons move around the nucleus in different orbits, closer or further away according to their energy. Planetary

· Modern – Electron Cloud – An atom’s electrons move like a particle and a wave, not keeping to neat orbits like Bohr’s theory.

· Protons: positive charge, in the nucleus, the atomic number.

· Electrons: negative charge, outside cloud, equal to protons.

· Neutrons: no charge, in the nucleus, mass – atomic number

· Ions: An atom gains (negative) or loses (positive) electrons.

· Isotope: An atom gains or loses neutrons. (changes mass only)

Physical Science Fact Sheet 2 – SOLs 5-7, 10

SOL 5: Changes in Matter

· Physical Changes alter the appearance of a substance, but do not make something new.

· Examples: melting, boiling, breaking, dissolving

· Chemical Changes produce a new substance through a chemical reaction.

· Examples: Burning, rusting, digesting, reacting

· Endothermic (Take in heat), Exothermic (Give off heat)

· Law of Conservation of Matter: Matter cannot be created or destroyed.

· Nuclear Changes alter the center nucleus of an atom.

· Fusion: combining hydrogen into helium. (Stars)

· Fission: splitting uranium atoms for energy.

· Nuclear Power Plants, Nuclear Weapons

· Nuclear Energy Pros: Efficient energy, no pollution, alternative to fossil fuels.

· Nuclear Energy Cons: radioactive waste must be safely stored.

SOL 7: Heat and Temperature

· Temperature is the average kinetic energy of a substance.

· Celsius: Water Boils (100), Water Freezes (0)

· Kelvin: No negatives. Absolute Zero is 0 Kelvin.

· Heat is total energy and transfers from hotter to cooler objects.

· Conduction: Heat transfer through a solid by touch.

· Convection: Heat transfer through liquid/gas by currents.

· Radiation: Heat transfer through empty space by waves.

SOL 6: Energy

· Energy is the ability to do work.

· Potential Energy is stored energy.

· Chemical – Energy in food, fuel, and living things.

· Nuclear – Energy in the nucleus of every atom.

· Gravitational – Energy of heights.

· Stored Mechanical – An object ready to move.

· Kinetic Energy is the energy of motion.

· Electrical – Energy from moving electrons.

· Thermal – Energy from moving atoms. (heat)

· Sound – Energy from vibrations.

· Mechanical – Energy from a moving object.

· Radiant – Energy from electromagnetic waves.

· Law of Conservation of Energy: Energy cannot be created nor destroyed, only transformed.

· Friction between surfaces causes a loss of energy from an energy transformation as heat. (wasted energy)

· Flashlight: chemical to electrical to radiant

· Microwave: electrical to radiant

· Human: chemical to mechanical

SOL 10: Force and Motion

· Speed is a change in distance over time. (d/t)

· Velocity is speed with direction.

· Acceleration is a change in velocity over time.

· Force is any push or pull on an object. (Newtons)

· Newton’s 1st Law: Objects at rest stay at rest, objects in motion stay in motion, unless acted on by outside forces. (Inertia)

· Newton’s 2nd Law: The greater the mass of an object, the greater the force needed to accelerate it.

· Mass: The amount of matter in an object.

· Weight: The force of gravity acting on a mass.

· Newton’s 3rd Law: For every action, there is an equal and opposite reaction force.

· Work is the use of force to move an object some distance. (Joules)

· Power is the rate (how fast) at which work is being done. (Watts)

· Simple Machines make work easier by changing the size or direction of the applied force.

· Ex: Wedge, Pulley, Inclined Plane, Screw, Wheel & Axle, Lever.

Physical Science Fact Sheet 3 – SOLs 8-9,11

SOL 8: Sound Waves

· Sound has to travel through a medium. (Fastest through Solid)

· Pitch is how high or low a sound is. (Determined by Frequency)

· Frequency is the number of waves per second. (Hz)

· Loudness is determined by amplitude (energy of a wave). (dB)

· Echolocation is the use of echoes by animals to find objects.

· Sonar is an electronic echolocation to locate objects underwater.

· Ultrasounds can be used to produce images inside the body.

· Resonance is the vibration of an object at its natural frequency.

· Tacoma Narrows Bridge, Musical Instruments, etc

· Doppler Effect: change in pitch when a sound passes an object.

· Interference: when sound waves combine.

· Constructive: produces louder sounds.

· Destructive: sounds cancel each other out.

SOL 9: Light Waves

· Electromagnetic waves (light) do not require a medium to travel through. They can travel through empty space (vacuum).

· Light moves fastest through empty space -> gas -> liquid -> solid

· High frequency waves have more energy, and are dangerous.

· Light can be absorbed (taken in) or reflected off a surface.

· The color of an object is determined by the light it reflects.

· Refraction is the bending of light as it changes speed moving through one medium to another.

· Diffraction is the bending of light around corners.

· Law of Reflection: The angle at which light hits a surface is the same angle it bounces off.

SOL 11: Electricity and Magnetism

· Static: the build up of electric charges by friction or other means.

· Like charges repel, opposite charges attract.

· Static Discharge: a release of electric charge. (shock, lightning)

· Current is the rate (how fast) of flow of electric charges. (V/R)

· Voltage is the amount of energy behind a moving charge.

· Resistance is the opposition to the flow of moving charges.

· Conductors allow heat and electricity through easily. (Metals)

· Insulators do not allow heat and electricity through easily.

· Ex: wood, plastic, rubber, paper, glass

· Semi-conductors behave as a conductor and insulator.

· Ex: Silicon, germanium. (Metalloids)

· Series Circuit: All devices connected in one path, all sharing the same current. (Dimmer bulbs, Holiday Lights)

· Parallel Circuit: All devices connected on their own path, each with its own full current. (Brightest bulbs, Home circuits)

· Electromagnet: an iron core wrapped with a current carrying wire to create a magnetic field.

· Electric Motor: converts electrical energy to mechanical energy.

· Generator: converts mechanical energy to electrical energy.

· AC moves e- back and forth; DC moves e- in one direction.