Cobalt Compounds and Sulfide Chemistry

The video tutorial explains how to write the formula for cobalt 6 sulfide. It begins by identifying the element symbols for cobalt and sulfur, and explains the significance of the Roman numeral indicating cobalt's charge. The tutorial then discusses the charges of the elements and how they must balance to form a neutral compound. By using three sulfide ions, the charges balance to zero, resulting in the formula CoS3. The video also covers how to name the compound based on its formula, emphasizing the importance of indicating the charge of cobalt in the name.

What is the element symbol for cobalt?

• Co

• Cb

• Cu

• Ca

What charge does the Roman numeral VI indicate for cobalt?

• 2+

• 4+

• 6+

• 8+

Which group is sulfur in on the periodic table?

• Group 16

• Group 14

• Group 15

• Group 17

How many sulfide ions are needed to balance the charge of one cobalt ion in cobalt 6 sulfide?

• 4

• 2

• 1

• 3

What is the formula for cobalt 6 sulfide?

• Co2S3

• CoS2

• CoS

• CoS3

Why is it important to include the charge of cobalt in the name of cobalt 6 sulfide?

• To specify the color of the compound

• To denote the physical state of the compound

• To show the oxidation state of cobalt

• To indicate the number of sulfur atoms