| A | B |
|---|
| matter | anything that has mass and takes up space |
| pure substance | a substance that is made up of only one type of particle - each piece is the same throughout |
| mixture | a substance that is made up of more than one type of particle |
| mechanical mixture | a mixture in which the different parts are easily visible |
| solution | a mixture in which the different parts are not visible - looks like a pure substance |
| colloid | a mixture in which tiny particles of one substance are suspended in another - can not be separated easily |
| suspension | a mixture in which tiny particles of one substance are suspended in another - can be separated easily |
| solid | one of the states of matter. Has a defined shape and volume, and has relatively low energy |
| liquid | one of the states of matter. Has a defined volume but no defined shape, and has more energy than a solid but less than a gas |
| gas | one of the states of matter. Has no defined shap or volume - takes on the shape and volume of its container, and has relatively high energy |
| melting | the transition from the solid to the liquid state of matter |
| freezing | the transition from the liquid to solid state of matter |
| evaporation | the transition from the liquid to the gas state of matter |
| condensation | the transition from the gas to the liquid state of matter |
| sublimation | the transition from solid state directly to the gas state, without becoming a liquid in between |
| deposition | the transition from the gas state directly to the solid state, without becoming a liquid in between |
| physical property | properties that can be measured or observed without changing the makeup of a substance (color, lustre, boiling point, solubility, etc.) |
| chemical property | properties that can be seen in the way a substance changes when it reacts chemically (what it reacts with, what it forms, etc.) |
| physical change | a change that is usually easily reversible, and does not change the makeup of a substance - it is the same substance after the change as before |
| chemical change | a change that is not easily reversible, and the chemical makeup of the substance involved is changed - the substance present at the end of the change is different from what was there at the start |
| element | a pure substance in which the particles are made of only one type of atom - can not be broken down into a simpler substance |
| periodic table | a chart in which all known elements are organized into rows and columns according to atomic number |
| period | a horizontal row in the periodic table - elements in a period have the same number of electron shells |
| group/family | a vertical column in the periodic table - elements that are in the same group have the same number of electrons in their outer shell |
| metal | a shiny, malleable element that conducts electricity and is solid at room temperature (except mercury) - found below and to the left of the staircase |
| non-metal | a dull, non conductive element that is often a gas or solid at room temperature (except bromine) - found above and to the right of the staircase |
| metalloid | elements found along the staircase of the periodic table that can take on metallic or non-metallic properties |
| alkali metals | group 1 elements - the most reactive elements - react violently with water and air |
| alkaline-earth metals | group 2 elements - also react with water and air, but not as violently as the alkali metals |
| halogens | group 17 elements, the most reactive non-metals - react well with alkali metals |
| noble gases | group 18 elements - the most stable and unreactive of all elements on the periodic table - do not react with anything |
| atomic number | the number found in the top left corner of the box on the periodic table - is equal to the number of protons in an element and is what defines that element |
| atomic mass number | the mass of an atom in atomic mass units - the sum of the number of protons and neutrons |
| atom | the basic building block of all matter - different elements are made of different types of atoms |
| proton | a positively charged subatomic particle found in the nucleus (mass of 1 amu) |
| electron | a negatively charged subatomic particle found orbiting around the nucleus in electron shells (1/2000th the mass of a proton or neutron) |
| neutron | a neutrally charged subatomic particle found in the nucleus (mass of 1 amu) |
| electron shell | an energy level outside the nucleus in which electrons are found |
| nucleus | the densely packed, positively charged center of the atom, made up of protons and neutrons |
| compound | two or more elements that are bonded together in a fixed ratio |
| chemical formula | a way of describing a chemical compound using element symbols and subscripts to indicate how many of each atom are present |
| ionic compound | containing a metal and a non-metal, a compound in which the metal becomes positively charged and the non-metal becomes negatively charged |
| molecular compound | contains a non-metal and a non-metal, and atoms share electrons as opposed to gaining or losing electrons |
| prefix | a part that comes before the name of an element (in molecular compounds only) that indicates how many of that atom are present in the compound (mono, di, tri, tetra, penta) |
| chemical reaction | a process in which one or more substances (called reactants) are converted into one or more different substances (called products) |
| endothermic | requiring energy to be put in. An endothermic reaction absorbs energy from its surroundings, thus feeling cold to the touch |
| exothermic | releasing energy. An exothermic reaction is one that releases energy into its surroundings, thus feeling hot to the touch |
| combustion | a highly exothermic chemical reaction involving oxygen and some sort of fuel, of which the products are carbon dioxide and oxygen |
| corrosion | a chemical reaction involving oxygen reacting with a metal, in which a metal oxide is formed |
| cellular respiration | a chemical reaction taking place inside animals in which oxygen reacts with a carbon based fuel (usually glucose) to produce carbon dioxide and water, which releases energy to be used in the body |
| conservation of mass | mass can not be created or destroyed in a chemical reaction. Therefore the mass of the products side must equal the mass of the reactants side |
| catalyst | a substance that is present with the reactants, and helps to speed up a reaction, but is not used up in the reaction |
| enzyme | a biological catalyst - proteins found in all cells that help reactions take place faster |
| rate of reaction | the speed at which a reaction occurs - the time it takes for reactants to completely turn into products |
| WHMIS | workplace hazardous materials information system - a set of symbols used to display the hazards of chemicals |
| solubility | the ability of a substance to dissolve in a solvent (often water) |
| element symbol | usually a 1 or 2 (sometimes 3) letter abbreviation for an element. Often comes from the beginning of the elements name or its latin name |
| ion | a charged particle. Has either gained or lost electrons to become positively or negatively charged |
| reactants | the substances that are present at the beginning of a chemical reaction |
| products | the new substance(s) that are created during a chemical reaction and are thus present at the end of the reaction |
