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any object that has a definite shape and has tightly packed molecules


a state of matter that can be easily poured and takes the shape of its surroundings


a state of matter that is almost always invisible and expands freely

physical change

a type of change in matter that can always be changed back

chemical change

another type of change that can not be changed back and causes a change in the chemicals


anything that takes up space and has weight (mass)


matter that is made up of a single type of particle


the simplest form of matter

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