Chapter 9, Section 1, Page 258 260

Chapter 9, Section 1, Page 258 – 260

An atom is made up of three things.

1 A proton i. The number of protons is the ATOMIC NUMBER ii. Protons are made up of quarks iii. Protons have a positive one charge (+1), exactly 2 A Neutron i. The number of neutrons is determined by subtracting the atomic number (see above) from the atomic mass (higher number), which follows the “-“ symbol of atoms ii. Neutrons are also made up of quarks iii. Neutrons have a charge of exactly “0”. They are neutral iv. The number of neutrons, plus the number of protons, equals the atomic mass

3 An Electron i. An almost massless particle ii. Charge of exactly negative one (-1) The Nucleus of an atom has a huge collection of positive particles in it. Why does it not blow itself apart (since similar charges repel, and all the protons have the same charge)?

The answer is the STRONG NUCLEAR FORCE. Four Forces of Nature

Gravity ~ weakest of all. Almost nothing is known about it. It is probably carried by a particle called a graviton. Electromagnetic ~ combination of electricity and magnetism. It is carried by the interaction of the electrical/magnetic fields. Weak Nuclear force ~ keeps atoms from changing elements. Strong Nuclear ~ holds the atom together. This is the strongest of all of the forces, and is the one broken with nuclear reactions.

http://aether.lbl.gov/www/tour/elements/stellar/strong/strong.htm l