Matter and Atoms Flashcards
vocab
Anything that has mass and takes up space.
Matter
A small particle that is that is the building block of matter.
Atom
Matter with a composition that is always the same.
Subtance
A substance made of only one kind of atom.
element
Two or more atoms that are held together by chemical bonds and acts as a unit.
molecule
Two or more atoms that are held together by chemical bonds and acts as a unit.
compound
Matter that can vary composition.
mixture
A mixture in which the substances are not evenly mixed.
heterogeneous mixture
A mixture in which two or more substances are evenly mixed but not bonded together.
Homogeneous mixture
The region at the center of an atom that contains most of the mass of the atom
nucleus
A positively charged particle in the nucleus of an atom.
proton
An uncharged particle in the nucleus of an atom.
neutron
electron
A negatively charged particle that occupies the space in an atom outside the nucleus.
electron cloud
The region surrounding an atom’s nucleus where one or more electrons are most likely to be found.
atomic number
The number of protons in the nucleus of an atom of an element.
isotope
One of two or more atoms of an element having the same number of neutrons.
ion
An atom that has a charge because it has a charge because it has gained or lost electrons.
