Cobalt and Sulfide Compounds

The video tutorial explains how to write the formula for cobalt(IV) sulfide. It begins by identifying the element symbols for cobalt and sulfide, noting that cobalt has a charge of 4+ and sulfide has a charge of 2-. The tutorial then discusses how to balance these charges to form a neutral compound, resulting in the formula CoS2. Finally, it covers how to name the compound based on its formula, emphasizing the importance of understanding ion charges and balancing them to achieve neutrality.

What is the element symbol for cobalt?

• Co

• Cb

• Ca

• Cu

What is the charge of the sulfide ion?

• 1-

• 2-

• 3-

• 4-

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

• 4

• 3

• 1

• 2

What is the net charge of the compound cobalt four sulfide?

• 2-

• 2+

• 0

• 1+

What is the correct formula for cobalt four sulfide?

• CoS2

• Co2S

• CoS

• Co2S3

Why is the Roman numeral 'four' used in the name cobalt four sulfide?

• It indicates the number of cobalt atoms.

• It represents the charge of the cobalt ion.

• It shows the number of sulfide ions.

• It is a random numeral.