Question

table 2.4 common non - metal ions
element name element symbol ion symbol ion name
nitrogen n n³⁻ nitride
oxygen o o²⁻ oxide
fluorine f f⁻ fluoride
phosphorus p p³⁻ phosphide
sulfur s s²⁻ sulfide
chlorine cl cl⁻ chloride
selenium se se²⁻ selenide
bromine br br⁻ bromide
iodine i i⁻ iodide
learning check

1. explain how ionic compounds are named.
2. name these ionic compounds.

a) nabr b) lif c) mgbr₂ d) ali₃ e) k₂s

1. how do you know how many of each type of element there are in an ionic compound?
2. write the chemical formula for these ionic compounds.

a) cesium fluoride d) potassium phosphide
b) strontium chloride e) aluminum nitride
c) barium oxide (hint: the charges are the same)

Explanation:

1. Ionic compounds are named by writing the name of the metal first, followed by the name of the non - metal with its ending changed to “-ide”. If the metal has multiple oxidation states, a Roman numeral in parentheses is used to indicate the charge of the metal ion.

2.

• a. Sodium bromide
• b. Lithium fluoride
• c. Magnesium bromide
• d. Aluminum iodide
• e. Potassium sulfide

1. The subscripts in the chemical formula of an ionic compound indicate the number of each type of element. The subscript applies to the element symbol it follows. If there is no subscript, it is assumed to be 1.

4.

• a. CsF
• b. SrCl₂
• c. BaO
• d. K₃P
• e. AlN

Answer:

1. Ionic compounds are named with metal first and non - metal with “-ide” ending (and Roman numerals for metals with variable oxidation states).

2.

• a. Sodium bromide
• b. Lithium fluoride
• c. Magnesium bromide
• d. Aluminum iodide
• e. Potassium sulfide

1. Subscripts in the chemical formula show the number of each element.

4.

• a. CsF
• b. SrCl₂
• c. BaO
• d. K₃P
• e. AlN