Term | Definition |
Activation Energy | What is needed to start a chemical reaction |
Arrow | you read the arrows as yields in a chemical equation or formula |
Characteristics of a chemical reaction | Changes in energy or changes in properties (produce a gas (bubbles form), color change, precipitate forms or temperature change) |
Chemical changes | Alter the chemical properties of matter new substances with new properties are formed |
Chemical equations | A shorter easier way to show chemical reactions by using symbols instead of words. |
Coefficient | A number placed in front of a chemical formula in an equation tells how many atoms or molecules of each reactant and product take part in the reaction. |
Conservation of matter | The amount of matter involved in a chemical reaction does not change the total mass of the reactants must equal the total mass of the products |
Consontration | amount of one material in a given amount of another material |
Temperature | Higher heat causes faster reactions |
Surface area | Increased surface area= increased reaction |
Catalysts | Materials that increase that rate of the reaction |
Enzymes | Biological catalysts |
Inhibitors | Decreases the rate of the reaction |
Decomposition Reaction | A compound breaks down into simpler substances |
Endothermic Reaction | An observable change in energy that shows a chemical reaction took place a reaction that takes heat from the solution absorbs energy makes it feel cooler |
Exothermic Reaction | An observable change in energy that shows a chemical reaction took place a reaction that releases heat gives off energy makes it feel warmer most chemical reactions are this type |
physical changes | alter only the physical properties of matter no new substances are formed can be change in size shape or color change in phase (by increasing or decreasing temperature solid liquid gas) |
Precipitate | A solid that forms from solution during a chemical reaction observable change that shows a chemical reaction took place |
Products | the materials you have after a chemical reaction written on the right side of the formula |
Reactants | the materials you have at the beginning of chemical reaction written on the left side of the formula |
Replacement Reaction | One part of a compound is displaced by an element or compound from another substance (also called displacement reaction) |
states of matter | Solid liquid and gas ( pp.46-50) |
Subscripts | Show the number of atoms or an element in a molecule or the ratio of elements in a compound |
Synthesis Reaction | Two substances combine to form a new compound ( also called composition reaction) |