Oxidation States and Selenate Ion

The video tutorial explains how to determine the oxidation numbers for elements in the selenate ion (SeO4^2-). It begins by identifying the ion's charge and explaining that the sum of oxidation numbers equals this charge. The video then focuses on calculating the oxidation number of selenium, using oxygen's known oxidation state. An equation is set up and solved, revealing selenium's oxidation number as +6. The tutorial concludes by summarizing the process and confirming the results.

What is the charge of the selenate ion?

• 2-

• 1-

• 4-

• 3-

When dealing with ions, what should the sum of the oxidation numbers equal?

• The atomic number

• The mass number

• The charge of the ion

• Zero

What is the usual oxidation state of oxygen in compounds?

• -2

• -1

• 0

• +1

How many oxygen atoms are present in the selenate ion?

• 4

• 5

• 3

• 2

What is the oxidation number of selenium in the selenate ion?

• +4

• +7

• +5

• +6

What is the result when you add the oxidation numbers of all elements in the selenate ion?

• 2-

• 1-

• 0

• 3-

Which element's oxidation number was unknown and needed to be calculated?

• Sulfur

• Oxygen

• Selenium

• Nitrogen