click below
click below
Normal Size Small Size show me how
Test 1
| Question | Answer |
|---|---|
| exothermic | reaction in which energy is released (explosions) |
| endothermic | reaction in which energy is absorbed (cold pack) |
| chemical reaction | process in which elements and/or compounds interact with one another to form more substances |
| product | chemical(s) produced as a result of a chemical reaction |
| reactant | starting material(s) in a reaction |
| density | d=m/v |
| mass | quantity of matter in an object |
| matter | anything that has mass and volume |
| quantity | something that has magnitude or size |
| volume | space an object occupies |
| weight | force of gravity acting on mass |
| allotrope | one of the number of different molecular forms of an element |
| atom | basic unit of matter |
| element | one of 10 simplest substances from which more complex substances are made |
| molecule | 2 or more atoms combined in a definite ratio, held together by covalent bonds, and is chemically neutral |
| acid | class of compounds whose water solutions taste sour, turn blue litmus paper red, and react with bases to form salts |
| base | class of compounds: taste bitter, feel slippery in water solution, turns red litmus paper blue, and react with acids to form salts |
| compound | pure substances composed of atoms from 2 or more different elements, ionic bonds (ex: water) |
| mixture | collection of 2 or more pure substances physically mixed together (ex: chicken soup, rocks in sand, iced tea, kool aid) |
| ion | atom or group of atoms with electrical charge (ex: Na^+) |
| inorganic compound | compounds that lack the element carbon |
| organic compound | compounds that contains element carbon |
| pH | numerical scale (0-14) used to express acidity or basicity; 0-7 is acid, 7 is neutral, 7-14 is base |
| chemical bond | force of attraction between different atoms that binds atom together |
| energy | capacity to do some type of work |
| heat | sum total of kinetic energy of the particles in a sample of the matter |
| kinetic energy | energy an object has because of its motion |
| potential energy | energy an object has because of its postition |
| specific heat | amount of heat energy requires to raise temperature of 1g of a substance by 1K |
| system | a specific portion of matter in a given region of space that has been selected for study during an experiment or observation |
| temperature | measure of average kinetic energy of particles in a sample of the matter |
| hypothesis | reasonable and testable explanation of observations |
| theory | well tested explanation of observation |
| scientific law | description of natural world that has proven reliable over time |
| accuracy | extent to which a measurement approaches true value of quantity |
| precision | extent to which series of measurement of same quantity made in same way agree with one another |
| solid | fixed volume, fixed shape, molecules vibrate slightly |
| liquid | fixed volume, takes shape of container, particles can pass through each other |
| gas | takes volume an shape of container, particles are rapid and random |
| difference between weight and mass | weight is the force of gravity acting on mass, while mass is the quantity of matter in an object. |
| physical change | change that affects only physical properties (ex: melting, boiling, freezing) |
| chemical change | change that produces one or more new substances (ex: rusting, precipitation, released gas, emission of light, color change, glow stick) |
| physical property | any property of matter that can be measured without changing its chemical nature (ex: mass, density, height, color, texture, boiling point) |
| chemical property | property of matter that can be observed only when substances interact (ex: flammability, volatility, radioactivity) |
| how are temperature and heat related? | heat is the sum of kinetic energy in a sample of the particles in the matter. temperature is the average kinetic energy in a sample of the particles in the matter. |