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chemical reactions
science
| Term | Definition |
|---|---|
| chemistry | is the study of properties |
| element | is a substance that cannot be broken down into any other substance by chemical or physical means |
| compound | is a substance made of two or more elements |
| mixture | made from two or more pure substances |
| solution | a well mixed mixture |
| physical change | a change that alter the form of appearance of a material |
| chemical change | a change in matter that produces a new substance |
| precipitate | a solid that forms during a chemical reaction |
| atom | the smallest particle of an element |
| molecule | the combination of two or more atoms |
| chemical bond | the force that holds atoms together |
| chemical equation | is a shorter easier way to show chemical reactions |
| subscript | shows the number of atoms of an element in a molecule |
| reactants | the material you have at the beginning of a chemical reaction |
| symbol | one or two letter symbol |
| coefficient | a number in front of a chemical formula in the equation |
| synthesis | when two or more substances combine to make a more complex substance |
| decomposition | a reaction that breaks down compounds into simpler products |
| exothermic reaction | a reaction that releases energy in the form of heat |
| endothermic reaction | a reaction that absorbs energy |
| activation energy | is the minimum amount of energy that has to be added to a start a reaction |
| concentration | is the amount of one material in a given volume of another material |
| catalyst | a material that increases the rate of a reaction by lowering the activation energy |
| enzymes | provide a surface on which reactions take place |
| inhibitor | a material used to decrease the rate of a reaction |
| fuel | a material that releases energy when it burns |