answer | question |
Activation energy | what is needed to start a chemical reaction |
arrow-> | you read the arrow as yields in a chemical equation or formula |
characteristics of a chemical reaction | changes in energy or changes in properties gas ,color change,precipitate forms or temperature change |
chemical changes | alter the chemical properties of matter ,new substances are formed |
chemical changes | alter the chemical properties of matter ,new substances are formed |
chemical equations | a shorter easier way to show chemical reactions by using symbols instead of words |
chemical equations | a shorter easier way to show chemical reactions by using symbols instead of words |
coefficant | a number placed in front of a chemical formula in a equation. tells how many atoms or molecules of each reactant and product take part in a reaction |
coefficant | a number placed in front of a chemical formula in a equation. tells how many atoms or molecules of each reactant and product take part in a reaction |
conservation of mass | 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. |
controlling rates of reaction | concentration temperature surface area catalyst enzymes and inhibitors |
concentration | amount of one material in a given amount of another material |
tempature | higher heat causes faster reactions |
surface area | increased surface area= increased reaction |
catalysts | materials that increases the rate of the reaction |
enzymes | biological catalysts |
inhibitors | decreases the rate of reaction |
decomposition reaction | a compound that breaks down into similar substances |
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 |
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 |
physical changes | alter only the physical properties of matter no new substances are formed can be 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 writtenm on the right side of the formula |
reactants | |
products | the materials you have after a chemical reaction writtenm on the right side of the formula |
reactants | the materials you have at the beginning of a chemical reaction written on the left side of the formula |
replacement reaction | one part of a compound is displaced by an element from another substance ( also called displacement reaction) |
states of matter | solid,liquid,gas |
subscripts | show the number of atoms of 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) |