Question

Given the chemical formulas of the following compounds, name each compound and state the rules you used to determine each name. • RbF • CuO • (NH4)2C2O4 (Note: C2O4– is called oxalate.)

Answer 1

The compounds are named as rubidium fluoride, copper(II) oxide, and ammonium oxalate using specific naming rules for ionic and molecular compounds.

Step-by-step explanation:

RbF is named rubidium fluoride. This compound is an ionic compound composed of the metal rubidium (Rb) and the nonmetal fluorine (F). When naming ionic compounds, the name of the metal is written first, followed by the name of the nonmetal with its ending changed to -ide.

CuO is named copper(II) oxide. This compound is also an ionic compound, consisting of the metal copper (Cu) and the nonmetal oxygen (O). In this case, the Roman numeral in parentheses after the metal name indicates the charge of the metal cation.

(NH4)2C2O4 is named ammonium oxalate. This compound is a molecular compound made up of the polyatomic ion ammonium (NH4) and the polyatomic ion oxalate (C2O4-). When naming compounds with polyatomic ions, the names of the ions should be memorized.

Answer 2

When naming an ionic compound, write the name of the cation, which is the metal first. Then, write the name of the anion, which is the nonmetal. However, you remove the last 2-3 letters and replace suffixes.

1. RbF --> Rubidium Fluoride
Change fluorine to fluoride
2. CuO --> Copper (II) Oxide
Change oxygen to oxide. Oxide has a charge of -2. Since no subscripts are written, it means they have the same opposite charge. So, we use Copper (II).
3. (NH₄)₂C₂O₄ ---> Ammonium Oxalate
NH₄ is ammonia, but we change it to ammonium for polyatomic ions.