← 9th Grade Physical Science Final Exam Export Options Alphabetize Word-Def Delimiter Tab Comma Custom Def-Word Delimiter New Line Semicolon Custom Data Copy and paste the text below. It is read-only. Select All Galaxy a group of individual stars, star systems, star clusters, dust and gas bound together by gravity Supernova an explosion so violent that the dying star becomes more brilliant than the entire galaxy Star a large glowing ball of gas in space which generate energy through nuclear fusion in its core constellation a group of stars that appear to form a pattern Pulsar a spinning neutron star that appears to give off strong pulses of radio waves Globular cluster a large group of older stars that usually lack sufficient amounts of gas and dust to form new stars nuclear fusion The way all stars produce energy the same way blue star the hottest stars which are 30,000 K. cooler The temperature of older stars What determines whether a star will form a black hole or a neutron star? the mass and density of the star during its death How are other galaxies moving in relationship to our galaxy? They are moving away from our galaxy The Big Bang Theory The most accepted theory of the origin of the universe? In the Big Bang theory, the universe's beginning size the universe began with a small amount of matter smaller than the period at the end of this sentence. Age of the universe 13.7 billion years old Explains the expansion of the universe the Big Bang theory hydrogen the original material (element) in the Big Bang theory What is happening to the size of the universe? It is getting bigger knowledge of the universe scientists have a good idea -- but with further study that idea may change Life cycle of the average star (like our Sun) nebula -- protostar -- main sequence star -- red giant -- planetary nebula -- white dwarf -- Black dwarf A star ends its life as what? A neutron star, a black hole, or a dwarf star what is the possible lifecycle of a super giant star? Supergiant -- supernova -- neutron star or black hole Black hole a region of space containing so much matter that it collapses into an infinitely dense point. Neutron star the dense remnant of a high mass star that has exploded as a supernova which are smaller and denser than white dwarfs. White Dwarf star a star about the size of the Earth that has about the same mass of the Sun. Black dwarf star a white dwarf that becomes too cool to glow in visible light Planetary nebula the glowing cloud of gas that surrounds a dying star Protostar a contracting cloud of gas and dust with enough mass to form a star Nebula a large cloud of gas and dust spread out over a large volume of space Dark matter matter that does not give off radiation. It cannot be seen directly, but its presence can be detected by observing its gravitational effects on visible matter Geo means earth Helio means sun Ecliptic plane is an imaginary plane containing the Earth's orbit Moon is a relatively small natural body in space that revolves around a planet astronomical units (AU Distance from the sun is measured Maria are low (dark), flat plains formed by ancient lunar lava flows. Meteoroids are chunks of rock that move through the solar system. phases The different shapes of the moon visible from Earth Waxing opening Waning closing eclipse the shadow of one body in space, like a planet or moon, falls on another. Umbra darkest part of the moon's shadow Penumbra a region of shadow that is less dark than umbra. Tides the regular rise and fall of ocean waters terrestrial planets are planets similar in structure to Earth Kuiper belt is a wide belt that extends from Pluto's orbit out to about 100 AU or more from the sun. Reactant a substance or molecule that participates in a chemical reaction Product a substance that forms in a chemical reaction Chemical energy the energy released when a chemical compound reacts to produce new compounds Exothermic reaction a chemical reaction in which energy is released to the surroundings as heat Endothermic reaction a chemical reaction that requires energy input Chemical equation a representation of a chemical reaction that uses symbols to show the relationship between the reactants and products Mole ratio the relative number of moles of the substances required to produce a given amount of product in a chemical reaction Synthesis reaction a reaction in which two or more substances combine to form a new compound Decomposition reaction a reaction in which a single compound breaks down to form two or more simpler substances Combustion reaction the oxidation reaction of an organic compound in which heat is released Single-displacement reaction a reaction in which one element or radical takes the place of another element or radical in a compound Double-displacement reaction a reaction in which a gas, a solid precipitate, or a molecular compound forms from the apparent exchange of atoms or ions between two compounds Free radical an atom or a group of atoms that has one unpaired electron Oxidation-reduction reaction any chemical change in which one species is oxidized (loses electrons) and another species is reduced (gains electrons) Catalyst a substance that changes the rate of a chemical reaction without being consumed or changed significantly Enzyme a type of protein that speeds up metabolic reaction in plants and animals without being permanently changed or destroyed Substrate the reactant in reactions catalyzed by enzymes Chemical equilibrium a state of balance in which the rate of a forward reaction equals the rate of the reverse reaction and the concentrations of products and reactants remain unchanged periodic table arrangement of elements in columns, based on a set of properties that repeat from row to row law of octaves repeating pattern of properties for every eighth element group up and down column on the periodic table period each row of the periodic table periodic law pattern of repeating properties that occurs in the periodic table atomic mass the weighted average of the masses of the isotopes of an element atomic mass unit one-twelfth the mass of a carbon-12 atom metals left of the zigzag line, shiny, malleable, ductile, good conductors of electric current, good conductors of thermal energy nonmetals elements that are usually dull in appearance, poor conductors of heat and electricity, gases at room temperature metalloids elements with properties that fall between those of metals and nonmetals valence electron electrons that occupy the outermost energy level, (highest energy level) alkali metals Group 1A elements that are extremely reactive and contain one valence electron alkaline earth elements Group 2A elements that very reactive and have two valence electrons halogen- a nonmetal in group 7A of the periodic table - most reactive nonmetal group noble gases one of the unreactive elements of group 18 of the periodic table transition metals elements that form a bridge between the elements on the left and right side of the periodic table Dalton's Theory Theorey that states that all matter is made up of indivisual particles called atoms, which cannot be divided. Nucleas A dense, positively charged mass located in the center of the atom. Proton A positively charged subatomic particle that is found in the nucleas of an atom. Electron A negatively charged subatomic particle that is found in the space outside the nucleas. Neutron A neutral subatomic particle that is found in the nucleas of an atom. Atomic Number Equals the number of protons in an atom of that element Mass Number The sum of the protons and netrons in the nucleas of that atom. Isotopes Atoms of the same element that have diffrent number of neutrons and diffrent mass numbers. Energy Levels The possible energies that electrons in an atom can have. Electron Cloud A visual model of the most likely locations for electrons in an atom. Electron Configuration The arrangement of electrons in an atom. Ground State When all the electrons in an atom have the lowest possible energies. Rutherford's Atomic Theory all of an atom's mass is concentrated in its nucleus Thompson's Model of the Atom Called the 'plum pudding' model. The atom is a lump of positively charged material with negatively charged electrons scattered in it. Dalton's Theory: 1. All elements are composed of atoms 2. All atoms of the same element have the same mass 3.Compounds contain atoms of more than one element 4.In a particular compound, atoms of diffrent elements always combine in the same way. Subatomic Particles protons, neutrons, and electrons Equation to find the number of nuetrons: Number of neutrons = Mass number - Atomic Number. Bohr's Model the atom is like the solar system and the planets orbiting the sun Solid A state of matter in which materials have a definite shape and definite volume Liquid A state of matter in which a material has a definite volume but not a definite shape Gases A state of matter in which a material does not have a definite shape or volume Kinetic Energy Energy of an object due to a motion. Kinetic Theory The constant motion of particles in a gas allows a gas to fill a container of any shape or size Pressure The result of a force distributed over an area Absolute Zero A temperature of 0 K Charles's Law The volume of a gas is directly proportional to its temperature in kelvins if the pressure and the number of particles of the gas are constant Boyle's Law The volume of a gas in inversely proportional to its pressure if the temperature and the number of particls are constant Combined Gas Law The relationship among the temperature, volume, and pressure of a gas when the number of particles are constant Phase Change The reversible physical change that occurs when a substance changes from one state of matter to antoher Endothermic Change The system absorbs energy from its surroundings Fusion Melting Evaporation Liquid to gas at temperatures below the substances boiling point Exothermic Change The system releases engery to its surroundings Vaporization Liquid to gas Condensation The phase change in which a substance changes froma gas or vapor to a liquid Sublimation The phase change in which a substance changes from a solid to a gas or vapor Deposition When gas or vapor changes directly into a solid without first changing into a liquid Atom The smallest particle of an element. Boiling Point Temperature at which a substance changes from liquid to gas. Chemical Change Occurs when a substance reacts with another substance forming one or more new substances. Chemical Property An ability to produce a change in the composition of matter. Colloid Contains some particles that are intermediate in size between the small particles in a solution and the larger particles in a suspension. Compound A substance that is made from two or more simpler substances and can be broken down into those simpler substances. Conductivity Ability of a material to allow heat and electricity to flow. Distillation Process that separates the substances in a solution based on their boiling points. Element A substance that cannot be broken down into simpler substances. Filtration A process that separates materials based on the size of their particles. Flammability Ability of a material to burn in the presence of oxygen. Heterogeneous Mixture The parts of the mixture are noticeably different from one another. Homogeneous Mixture The substances are so evenly distributed that it is difficult to distinguish one substance in the mixture from another. Malleability Ability of a solid to be hammered without shattering. Melting Point Temperature at which as substance changes from solid to liquid. Physical Change When a substance undergoes a change of state and/or shape, but the chemical properties remain the same. Physical Property Any characteristic of a material that can be observed or measured without changing the composition of the substance. Precipitate Any solid that forms and separates from a liquid mixture. Pure Substance Matter that always has the same composition. Reactivity How readily a substance combines chemically with other substances. Solution When substances dissolve and form a homogeneous mixture. Suspension A heterogeneous mixture that separates into layers over time. Viscosity The resistance to flow...thickness of a liquid. Mixture Properties can vary because the composition is not fixed. Hardness The resistance of a mineral to scratching. Density The ratio of the mass of a substance to its volume.