Bonding & Molecular Structure Day 1 - C.3.4 Write chemical formulas for ionic compounds and covalent compounds given their names and vice versa.

Critical Recall Atoms are neutral which mean they have the exact same number of protons and electrons. An element is defined by the number of protons in the nucleus of a single atom. An atom of an element can gain or loose electrons.

New Information An Ion is an atom or compound which has a positive or negative charge. This occurs when there is an uneven ratio of protons and electrons. A valence is the combining power of an element measured by the number of electrons total in an atom, element, or compound. You need to know valence charges by looking at the periodic table to properly write/name.

Intro. To Valences

Valence Practice Potassium  Chlorine  Oxygen  Xenon Beryllium  Nitrogen 

Cations are positive. (Cats have Paws) All positive ions (cations) consisting of only one element remain the same. Calcium (Ca)  Calcium (cation) Magnesium (Mg)  Magnesium (cation) Potassium (K)  Potassium (cation)

Cation Practice Cesium  Barium  Sodium  Lithium  Rubidium  Strontium 

Anions are negative little electron thieves. All negative ions (anions) consist of only one element (only one capital letter in the symbol) have a suffix of –ide. The –ide takes over at the end where: the second vowel exists within the word unless it contains a y. Chlorine (Cl)  Chloride (anion) Oxygen (O)  Oxide (anion) Phosphorous (P)  Phosphide (P-3 anion) -

Anion Practice Fluorine  Bromine  Iodine  Oxygen  Sulfur  Nitrogen 

Ionic Comic Strip Design!  Chem-is-try