Oxidation Numbers and Ionic Charges

The video tutorial explains how to find the oxidation number of chromium in SrCr2O7. It starts by identifying the oxidation numbers of strontium and oxygen, then sets up an equation to solve for chromium's oxidation number. The video concludes by confirming the oxidation number and mentioning an alternative method using the dichromate ion.

What is the overall charge of the compound SrCr2O7?

• Positive

• Negative

• Neutral

• Variable

What is the oxidation number of strontium in SrCr2O7?

• +1

• 0

• +2

• +3

What is the typical oxidation number of oxygen in compounds?

• -2

• 0

• -1

• +2

In the equation 2 + 2x - 14 = 0, what does x represent?

• Oxidation number of strontium

• Overall charge of the compound

• Oxidation number of oxygen

• Oxidation number of chromium

What is the oxidation number of chromium in SrCr2O7?

• +5

• +6

• +3

• +4

How many oxygen atoms are present in the dichromate ion Cr2O7?

• 8

• 7

• 6

• 5

What is the ionic charge of the dichromate ion Cr2O7?

• 2+

• 2-

• 1+

• 1-

Which method is suggested as easier for determining the oxidation number of chromium?

• Using the periodic table

• Using the charge of the dichromate ion

• Using the oxidation number of strontium

• Using the oxidation number of oxygen