lesson 5-7

the smallest unit of an element, each element is made up of only 1 kind of atom.

the postitively charged center of an atom

a particle that is smaller than the atom.

negatively charged particle which orbits the nucleus of an atom

a positively charged particle inside the nucleus of an atom

uncharged particle that is part of almost every atomic nucleus

all matter consist of tiny atoms that are indisvible

discovered electrons in atoms

discovered the nucleus with a positive charge

electrons move around the nucleus in orbits of fixed sizes and energies

solid, hard, incompressible, and indestructible

electron, neutron and proton

equal to the number of electrons as well as protons in a neutral atom

equal to the sum of the protons and neutrons

hydrogen

helium

lithium

beryllium

boron

carbon

nitrogen

oxygen

fluorine

neon