physical science fact sheets · physical science fact sheet 1 – sols 2-4 sol 2: classification of...

Physical Science Fact Sheet 1 – SOLs 2-4

SOL 2: Classification of Matter

• All matter is made of particles called atoms. o An element is a pure substance made of 1 type of atom

that cannot be broken down further. o A compound is a pure substance made of more than 1

type of atom chemically combined. § Organic compounds have C and H.

o 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. o 1st: Up to 2 electrons o 2nd: Up to 8 electrons o 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. o Family 1: 1 Valence, lose 1 to reach stability. o Family 2: 2 Valence, lose 2 to reach stability. o Family 13: 3 Valence, lose 3 to reach stability. o Family 14: 4 Valence, gain/lose 4 to reach stability. o Family 15: 5 Valence, gain 3 to reach stability. o Family 16: 6 Valence, gain 2 to reach stability. o Family 17: 7 Valence, gain 1 to reach stability. o 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). o 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). o Halogens are the most reactive nonmetals. (Family 17) o 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. o Examples: melting, boiling, breaking, dissolving

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

o Examples: Burning, rusting, digesting, reacting o 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.

o Fusion: combining hydrogen into helium. (Stars) o 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.

o Celsius: Water Boils (100), Water Freezes (0) o Kelvin: No negatives. Absolute Zero is 0 Kelvin.

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

o Conduction: Heat transfer through a solid by touch. o Convection: Heat transfer through liquid/gas by currents. o Radiation: Heat transfer through empty space by waves.

SOL 6: Energy • Energy is the ability to do work.

• Potential Energy is stored energy.

o Chemical – Energy in food, fuel, and living things. o Nuclear – Energy in the nucleus of every atom. o Gravitational – Energy of heights. o Stored Mechanical – An object ready to move.

• Kinetic Energy is the energy of motion.

o Electrical – Energy from moving electrons. o Thermal – Energy from moving atoms. (heat) o Sound – Energy from vibrations. o Mechanical – Energy from a moving object. o 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. o Mass: The amount of matter in an object. o 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)

o 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.

o Tacoma Narrows Bridge, Musical Instruments, etc • Doppler Effect: change in pitch when a sound passes an object. • Interference: when sound waves combine.

o Constructive: produces louder sounds. o 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.

o 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.

o Ex: wood, plastic, rubber, paper, glass • Semi-conductors behave as a conductor and insulator.

o 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.