Ions

With the short class period, lesson 19 was distilled down to the key vocabulary words:

Ion: An atom (or group of atoms) that has a positive or negative charge because it has lost or gained electrons.

Cation: An ion with a net positive charge. Usually these are formed from metal atoms.

Anion: An ion with a net negative charge. Usually these are formed from nonmetal atoms.

We referred back to the Flame Test lab as practice using the new vocabulary terms.  For example, the compound sodium chloride, NaCl, consists of a cation (Na+) and an anio (Cl-).  Students then have the remainder of the class period to complete the practice problems in the textbook (homework on page 97, questions 1-16).