Science

Mass

Anything that takes up space or has mass

Atoms

Building blocks of matter

subatomic particles

protons, neutrons, electrons

Resides in nucleus (center of atom):

Protons and Neutrons

Exist around the nucleus:

Electrons

Protons

positive charge

Electrons

negative charge

Neutron

neutral no charge

How many atoms on earth?

92

valence electrons

electrons in the outermost shell

Element

A pure substance made of only one kind of atom

Compound

A substance made up of atoms of two or more different elements joined by chemical bonds

Molecule

Contains an exact number of atoms held together by chemical bonds

Chemical

Pure substance that contains only one element or compound

The three states of matter are

solid, liquid, gas

macroscopic properties

properties that can be measured

chemist

A scientist who studies matter and how it changes