Mastering Polyatomic Ions and Their Chemical Formulas

Mr. Millings explains how to name and memorize polyatomic ions, focusing on common ions seen in chemistry courses. He introduces key rules for understanding the 'ate' and 'ite' suffixes, as well as the 'per' and 'hypo' prefixes, which indicate the number of oxygen atoms in ions. The video also distinguishes between monatomic and polyatomic ions, providing strategies for memorization to aid in writing chemical formulas.

What is the chemical formula for ammonium?

• Cr2O7-

• SO4-

• ClO2-

• NH4+

According to the rule '8 is bigger than 8', what does a polyatomic ion ending in 'ate' have compared to one ending in 'ite'?

• Same number of oxygens

• One more oxygen

• One less oxygen

• Two more oxygens

Which of the following is the correct formula for chlorite?

• ClO3-

• ClO2-

• ClO4-

• ClO-

What is the difference in oxygen atoms between bromate and bromite?

• Bromite has one more oxygen

• Bromate has one more oxygen

• They have the same number of oxygens

• Bromate has two more oxygens

What does the prefix 'per-' indicate in a polyatomic ion?

• One less oxygen

• One more oxygen

• No change in oxygen

• Two more oxygens

Which of the following is the formula for perchlorate?

• ClO4-

• ClO2-

• ClO3-

• ClO-

What does the prefix 'hypo-' signify in a polyatomic ion?

• One less oxygen

• One more oxygen

• Two more oxygens

• No change in oxygen

If bromite has two oxygens, how many does hypobromite have?

• One

• Four

• Two

• Three

Which of the following is a monatomic ion?

• Perchlorate

• Chlorate

• Chlorite

• Chloride

What suffix indicates a single monatomic ion?

• ate

• per

• ite

• ide