Ionic Compounds and Ammonium Ions

The video tutorial explains how to write the formula for ammonium chromate by identifying the polyatomic ions involved, ammonium (NH4+) and chromate (CrO4^2-). It emphasizes the importance of balancing the ionic charges to achieve a net charge of zero, resulting in the formula (NH4)2CrO4. The tutorial provides a step-by-step approach to understanding the composition and charge balancing of ionic compounds.

What is the significance of recognizing the ending '-ium' in chemical names?

• It means the compound is organic.

• It denotes a gaseous state.

• It suggests the presence of a polyatomic ion.

• It indicates a metal element.

What is the chemical formula for the ammonium ion?

• NH2+

• NH4+

• NH5+

• NH3+

How can you find the formula for the ammonium ion if you haven't memorized it?

• By looking it up in a periodic table.

• By checking a table of polyatomic ions.

• By using a calculator.

• By asking a chemist.

What is the charge of the chromate ion?

• 1+

• 2+

• 1-

• 2-

Why is it important to balance the charges in an ionic compound?

• To make the compound reactive.

• To give the compound a pleasant color.

• To make the compound soluble in water.

• To ensure the compound is stable.

How many ammonium ions are needed to balance the charge of one chromate ion?

• One

• Two

• Three

• Four

What is the final chemical formula for ammonium chromate?

• (NH4)2CrO4

• NH4CrO4

• (NH3)2CrO4

• NH4CrO3