science ch 2 vocab Flashcards
The scientific study of the composition, structure, and properties of matter and the changes that matter undergoes.
Chemistry
Anything that has mass and takes up space.
Matter
A substance that cannot be separated or broken down into simpler substances by chemical means.
Element
The smallest unit of an element that maintains the properties of that element.
Atom
A substance made of atoms or two or more different elements that are chemically combined.
Compound
The smallest unit of a substance that keeps all of the physical and chemical properties of that substance.
Molecule
A combination of chemicals symbols and numbers to represent a substance.
Chemical formula
A sample of matter, either a single element or a single compound, that has definite chemical and physical properties.
Pure substance
A combination of two or more substances that are not chemically combined.
Mixture
The temperature and pressure at which a solid becomes a liquid.
Melting point
The temperature at which a liquid becomes a gas.
Boiling point
The ratio of the mass of a substance to the volume of a substance.
Density
The ability of a substance to combine chemically with another substance.
Reactivity
The ability of a substance to react in the presence of oxygen and burn when exposed to a flame.
Flammability
A change of matter from one form to another without a change in chemical properties.
Physical change
