Mastering Polyatomic Ions: Naming Compounds and Writing Formulas

This video tutorial by Mr. Millings covers how to name and write chemical formulas for compounds containing polyatomic ions. It begins with an introduction to polyatomic ions and the importance of memorizing common ions. The video then explains the rules for naming compounds with polyatomic ions, using the same rules as for type one and type two binary ionic compounds. It also covers how to write chemical formulas from given names, ensuring ionic charges add up to zero. The tutorial includes several example problems to illustrate these concepts and concludes with practice problems for viewers.

Why is it important to memorize common polyatomic ions?

• To impress your teacher

• To easily name and write chemical formulas

• To solve math problems

• To understand organic chemistry

What is the first step in naming a compound containing a polyatomic ion?

• Identify the anion

• Check the color of the compound

• Determine the type of metal

• Count the number of atoms

When naming a compound with a type 2 metal, what must be included?

• The metal's color

• The metal's atomic number

• The metal's melting point

• A Roman numeral indicating the charge

What is the key rule when writing chemical formulas for compounds with polyatomic ions?

• Avoid using parentheses

• Always start with the anion

• Use only single atoms

• Ensure the charges add up to zero

How do you handle polyatomic ions when adding subscripts in a chemical formula?

• Ignore them

• Add subscripts directly without parentheses

• Use parentheses around the ion before adding subscripts

• Add subscripts to the cation only

What is the chemical formula for iron(III) chlorate?

• Fe3(ClO3)2

• Fe2(ClO3)3

• Fe(ClO3)3

• FeCl3

How many ammonium ions are needed to balance the charge with sulfate in ammonium sulfate?

• Four

• Two

• One

• Three

What is the name of the compound with the formula NaNO3?

• Sodium nitrite

• Sodium nitrate

• Sodium sulfate

• Sodium phosphate

What is the charge of lead in the compound Pb(C2H3O2)2?

• 4+

• 1+

• 2+

• 3+

What is the name of the compound Sn(Cr2O7)2?

• Tin(V) dichromate

• Tin(IV) dichromate

• Tin(III) dichromate

• Tin(II) dichromate