matter
anything that has mass and takes up space.
chemistry
the study of matter.
physical property
a characteristic of a substance that can be observed without changing the substance into another substance.
chemical property
a characteristic of a substance that describes the ability to change into other substances.
physical change
any change that alters the form or appearance of a substance but does not make the substance into another substance.
chemical change
a change in matter that produces one or more new substances.
reactions
the substances that undergo change in a chemical reactions.
products
the new substances formed the reaction.
precipitate
a solid that forms from solution during a chemical reaction.
endothermic reaction
the total making and breaking of bonds results in a net absorption of energy.
exothermic reaction
the total making and breaking of bonds results in a net release of energy.
chemical equation
a short easy way to show a chemical reaction, using symbols instead of words.
conservation of matter
during a chemical reaction, matter is neither created nor destroyed.
open system
matter can enter from or escape to the surroundings.
closed system
matter is not allowed to enter or leave.
coefficient
a number placed in front of a chemical formula in an equation.
synthesis
when two or more elements or compounds combine to make a more complex substance
decomposition
occurs when compounds break down into simpler products.
replacement
when one element replaces another in a compound, or when two elements in a different compounds trade places.
activation energy
the minimum amount of energy needed to start a chemical reaction.
concentration
the amount of a substance in a given volume.
catalyst
a material that increases the rate of a reaction by lowering that activation energy.
enzymes
the cells in your body(as in living things) contain biological catalysts.
inhibitor
a material used to decrease the rate of a reaction.
combustion
a rapid reaction between oxygen and a fuel.
fuel
a material that releases energy when it burns.