Ammonium Ion and Iodide Compounds

The video tutorial explains how to write the formula for ammonium iodide. It begins by introducing the ammonium ion, a polyatomic ion not found on the periodic table, and emphasizes the importance of memorizing it. The ammonium ion is NH4+ with a charge of +1. Next, the video discusses the iodide ion, derived from iodine, a halogen with a -1 charge. The tutorial demonstrates how to combine these ions to form ammonium iodide (NH4I) with a net charge of zero. The video concludes with a summary and thanks to the viewers.

What is the first step in writing the formula for ammonium iodide?

• Memorize the periodic table.

• Calculate the molecular weight.

• Write the formula for the ammonium ion.

• Identify the charge of the iodide ion.

Which of the following best describes the ammonium ion?

• A metal ion with a variable charge.

• A diatomic molecule with no charge.

• A polyatomic ion with a positive charge.

• A single atom with a negative charge.

What is the chemical formula for the ammonium ion?

• NH2-

• NH4+

• NH3

• NH4-

Which group does iodine belong to on the periodic table?

• Group 17

• Group 2

• Group 18

• Group 1

What is the charge of the iodide ion?

• 1+

• 2+

• 2-

• 1-

How do the charges of ammonium and iodide ions combine to form a neutral compound?

• The charges do not need to balance.

• The charges add up to a negative value.

• The charges add up to a positive value.

• The positive charge of ammonium and the negative charge of iodide cancel each other out.

What is the final chemical formula for ammonium iodide?

• NH4I

• NH3I2

• NH3I

• NH4I2

Why is it important to ensure the net charge of a compound is zero?

• To increase the compound's solubility.

• To ensure the compound is stable.

• To make the compound more reactive.

• To decrease the compound's melting point.