Physical Sciences: Matter & Energy What is physical science? A. Physical science is a field of science that studies matter and energy. B. Physical science has 2 main branches: 1.PHYSICS: the study of how matter and energy interact Force, motion, robotics, nuclear energy, solar panels 2.CHEMISTRY: the study of the structure, makeup, and changes of matter chemicals, acids & bases, atoms, molecules, medicines
What is matter? A. OBJECT: an item or material thing made of matter. 1. All objects are made of matter. B. MATTER: anything that has mass and takes up space C. PROPERTIES: the characteristics used to describe matter 1. There are 2 major types of properties: a. PHYSICAL PROPERTIES: characteristics that can be observed without changing the matter * Includes size, texture, states, color, shape, mass, volume, buoyancy, density b. CHEMICAL PROPERTIES: characteristics that can be observed by changing the matter * Includes oxidation, burning, digestion
What is matter made of? A. All matter is made of atoms B. ATOM: the smallest part of matter. C. Atoms are made of three subatomic particles: 1. PROTON: a positive (+) subatomic particle 2. NEUTRON: a neutral subatomic particle 3. ELECTRON: a negative (-) subatomic particle There are two parts to an atom: 1. NUCLEUS: the center of an atom where neutrons and protons are located 2. ENERGY LEVELS: orbits where electrons are located
What is a molecule? A. MOLECULE: one or more atoms joined together to make a new type of matter 1. Molecules can be made of one kind of atom or different kinds of atoms. Oxygen we breathe is an example of one kind of atom in a molecule Water is an example of more than one kind of atom in a molecule 2. Molecules are held together by bonds B. Most matter on earth is made of different types of molecules bonded or mixed together.
What is a chemical formula? A. CHEMICAL FORMULA: way of writing a molecule using chemical symbols 1. Chemical symbols are letters: Carbon: C Helium: He Hydrogen: H Gold: Au Oxygen: O Iron: Fe Nitrogen: N Sodium: Na Chemical formulas are a combination of symbols and numbers to show how many atoms are used: Water: 2 Hydrogen, 1 Oxygen: H 2 O Carbon Dioxide: 1 Carbon, 2 Oxygen: CO 2 Ethane: 2 Carbon, 6 Hydrogen: C 2 H 6 Glucose: 6 Carbon,12 Hydrogen, 6 Oxygen: C 6 H 12 O 6
What are the 3 types of molecular matter? A. Molecular matter can be grouped into three main types: 1. ELEMENT: molecules made of one kind of atom; simplest substances in nature that cannot be broken down into smaller parts Oxygen is an example of an element 2. COMPOUND: molecules made up of two or more different types of atoms that are chemically joined together (can t be separated by physical means) Water is an example of compound 3. MIXTURE: a substance made up of two or more kinds of molecules that are physically mixed together (can be separated by physical means) Soil, air, pancake batter are examples of mixtures
How are molecules classified? A. Molecular compounds are classified in a number of different ways: 1. Compounds made with or without carbon: a. INORGANIC: molecules without carbon b. ORGANIC: molecules with carbon 2. Compounds that are large or small: a. MONOMERS: smaller molecules b. POLYMERS: large molecules All compounds are molecules, but not all molecules are compounds.
What are some physical properties of matter? A. Properties are characteristics used to describe matter. B. PHYSICAL PROPERTIES can be observed without changing matter into a new substances 1. Examples includes size, texture, states, color, shape, mass, volume, buoyancy, density 2. None of these examples change the matter into new matter An object s physical properties determine its use.
How are mass and volume physical properties? A. Two major physical properties of matter are mass and volume 1. MASS: the amount of matter an object contains a. Mass on earth is often measured using weight i. WEIGHT: a measure of the pull of gravity on an object ii. Mass and weight are measured in grams (g) 2. VOLUME: the amount of space an object takes up a. Volume is measured in liters (l) B. The mass and volume of matter affects other physical properties.
What are the states of matter? A. STATE OF MATTER: any of the four physical forms of matter. 1. SOLID: state of matter where molecules are tightly packed They have volume and shape 2. LIQUID: state of matter where molecules are loosely packed. They have volume but no fixed shape 3. GAS: state of matter where molecules are spreading out. They have no fixed volume and no fixed shape
What are the states of matter? B. Matter can change from one state to another. This change is often caused by a change in heat energy. 1. FREEZING: a change from liquid to solid Liquid must be cooled 2. MELTING: a change from solid to liquid. Solid must be heated 3. EVAPORATION: a change from liquid to gas liquid must be heated 4. CONDENSATION: a change from gas to liquid gas must be cooled
What are other physical properties of matter? A. DENSITY: the amount of matter packed into an object. 1. Very dense objects have a lot of matter for their volume. 2. Less dense objects have little matter for their volume. 3. The equation for density is m v = D B. DISPLACEMENT: the pushing aside of water by an object 1. Larger and denser objects push more water aside than smaller less dense objects 2. Displacement can be used to measure volume C. BUOYANCY: the ability for an object to float in water. 1. As gravity pulls down on an object, the water pushes up on the object 2. Buoyancy can be described in three ways: a. Positive Buoyancy: floats at the surface b. Negative Buoyancy: sinks to the bottom c. Neutral Buoyancy: hangs between surface and bottom 3. Buoyancy is related to displacement a. The more buoyant, the less displacement b. The less buoyant, the more displacement
What are other physical properties of matter? D. ELECTRICAL CONDUCTIVITY: a property of matter that allows the flow of electricity 1. CONDUCTOR: any material that allows the movement of electrons 2. Atoms in conductors have electrons that move from one atom to another. E. ELECTRICAL RESISTIVITY: a property of matter that prevents or resists the flow of electricity 1. RESISTOR: any material that slows or prevents the movement of electrons Atoms in resistors do not have electrons that move from one atom to another. F. ELECTROLYTES: chemicals in a battery that cause chemical reactions to push electrons through a circuit 1. Sodium, potassium, magnesium, acids and bases are all good electrolytes 2. Salt water and citric acid in oranges are all electrolytes used in the stations that caused the flow of electricity
What are other physical properties of matter? G. FLUIDITY: the ability of a substance to flow. 1. Solids have no fluidity because the molecules are too tightly packed to change shape easily 2. Liquids and gases are considered fluids because their molecules are loose enough to change shape. H. VISCOSITY: the way in which a liquid flows 1. Some liquids are able to flow better than others depending on how thick or thin they are 2. Low viscosity means a liquid is thin and flows easily, high viscosity means a liquid is thick and does not flow easily I. SPECIFIC GRAVITY: the density of a liquid as compared to water. 1. If a liquid is very dense, there is more matter in the liquid for gravity to pull down on 2. Liquids are tested against water for their specific gravity