Bell work – what is an atom? Particle that makes up all matter.

Smallest unit that still has the properties of the element. 1) What is an atom? Smallest unit that still has the properties of the element. What does atom really mean? indivisible or uncuttable

Proton Neutron Electron 2) What makes up an atom? Proton Neutron Electron

3) What is a subatomic particle? Particles that make up the atom

Number of protons equals the number of electrons 4) Why are atoms neutral? Number of protons equals the number of electrons

5) Describe the following: Atomic number – Atomic mass – Proton – Neutron – Electron – Number of protons Number of protons and neutrons Positive Where is it located? Where is it located? Where is it located? Nucleus Neutral Nucleus Negative Outside

6) What is a Valence electron? Electron in the outer shell; bonding electrons

7) What is an Isotope? Atoms of the same element that have different mass/different # neutrons

8) What subatomic particle has about the same mass a proton, but with no charge? neutron

9) What subatomic particle has about the same mass a proton, but with no charge? electron

10) What subatomic particles are found in the nucleus? Proton and neutron

11) Isotopes of an element contain different numbers of which subatomic particles? neutron

Mass - protons = neutrons oxygen 8 8 8 16 8 nitrogen 7 7 7 14 7 6 6 C 6 12 6 18 22 18 Argon 18 40 K 19 20 39 19 Potassium Fe Iron 26 26 30 56 Fluorine 9 10 19 9