STRUCTURE OF MATTER According to the modern atomic model, protons and neutrons are found in the nucleus, and electrons are found outside the nucleus in a region called the _____________. Protons have a _________ charge. Electrons have a ________ charge. __________ are neutral, they have no charge.

Protons and Neutrons are made up of smaller particles called ______ Protons and Neutrons are made up of smaller particles called ______. There is an ________ and a _________ held together by particles called ______. _______ have more up quarks than down quarks. ________ have more down quarks than up quarks.

ELECTRON ENERGY LEVELS The first energy level, closest to the nucleus, can hold only ___ electrons (e-). The second energy level can hold only ___ e-. The third energy level is stable when it has__ e-. (can actually hold 18 in all, but only after the fourth energy level has at least 2)

Maximum # of e- the orbital can contain 1 s2 Energy level 2 s2 p6 3 s2 p6 d10 4 s2 p6 d10 f14 5 s2 p6 d10 f14 6 s2 p6 d10 7 s2 p6

IONS _______ atoms (or groups of atoms) are called ions. An atom becomes charged by either gaining or losing one or more _________. An atom that has lost one or more e- is a ________ ion (cation). The atom now has more protons than e-. An atom that has gained one or more e- is a ________ ion (anion). The atom now has more e- than protons.

Generally, atoms do not gain or lose protons. An atom will become an ion only by gaining or losing e-. The number of protons (or neutrons) will only change during nuclear fission, nuclear fusion, or radioactive decay. What charge will an atom have if it loses 3 e-? What charge will an atom have if it gains 2 e-?

A ________ is any two or more __________ elements combined. The smallest unit of any ________ (example: water) that still retains the properties of the substance is a ________. A __________ is any two or more atoms combined by sharing electrons. (non-metals only, even two of the same element) A ________ is any two or more __________ elements combined. Chemical reactions involve ___________ of atoms, not the destruction or creation of them.

FORMULA a representation of one ____________ of a substance by showing the ________ of each element in the substance and the _________ of each element in the molecule Example: H2O is the formula for water because it represents one molecule of water. If you broke the substance down any farther, it would not be water.

If you have a formula like C7H5(NO2)3 , you would have __ carbon atoms, __ hydrogen atoms, __ nitrogen atoms, and __ oxygen atoms. Any time you have atoms inside a parenthesis ( ) with a subscript number after the ( ), you multiply the number after the ( ) by the number of each element inside the ( ) to obtain the total number of atoms for each element inside the ( ).

The group of atoms inside the ( ) is called a _________ ____. has a charge more than one