Ionic Compounds and Their Charges

The video tutorial explains how to find the formula for the ionic compound lithium selenide. It begins by identifying the charges of lithium and selenium ions using the periodic table. Lithium, in group 1, has a charge of +1, while selenium, in group 16, has a charge of -2. The tutorial then demonstrates how to balance these charges to achieve a net charge of zero, resulting in the formula Li2Se for lithium selenide.

What is the main goal when finding the formula for an ionic compound?

• To achieve a net charge of zero

• To maximize the number of atoms

• To achieve a net charge of one

• To minimize the number of atoms

In which group is lithium found on the periodic table?

• Group 2

• Group 1

• Group 16

• Group 17

What charge does a lithium ion typically have?

• Positive two

• Negative two

• Negative one

• Positive one

In which group is selenium found on the periodic table?

• Group 16

• Group 17

• Group 2

• Group 1

What charge does a selenium ion typically have?

• Positive one

• Negative two

• Positive two

• Negative one

What is the charge of two lithium ions combined?

• Zero

• Positive one

• Negative two

• Positive two

How many lithium ions are needed to balance one selenium ion?

• Four

• Three

• Two

• One

What is the net charge when two lithium ions and one selenium ion are combined?

• Positive one

• Negative one

• Zero

• Positive two

What is the correct formula for lithium selenide?

• LiSe

• Li2Se

• Li2Se2

• LiSe2

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

• To make the compound more reactive

• To increase the compound's weight

• To ensure the compound is stable

• To decrease the compound's weight