Formal Charges and Valence Electrons

The video tutorial explains how to calculate the formal charges of atoms in the sulfate ion (SO4 2-). It begins with an introduction to the sulfate ion and the concept of formal charge. The tutorial then details the calculation of formal charges for each oxygen atom, highlighting the differences between non-bonding and bonding electrons. The symmetrical nature of the ion is discussed, showing that some oxygen atoms have the same formal charge. Finally, the formal charge of the sulfur atom is calculated, concluding with a summary of the charges for the entire ion.

What is the charge of the sulfate ion?

• 2+

• 2-

• 1+

• 1-

How many valence electrons does oxygen have?

• 7

• 6

• 5

• 4

What is the formal charge of the first oxygen atom in the sulfate ion?

• +1

• -1

• 0

• -2

How many non-bonding electrons are present in the first oxygen atom?

• 2

• 4

• 6

• 8

What is the formal charge of the second oxygen atom in the sulfate ion?

• -1

• 0

• -2

• +1

How many bonding electrons are shared between sulfur and the second oxygen atom?

• 8

• 6

• 4

• 2

What is the group number of sulfur in the periodic table?

• 17

• 16

• 14

• 15

How many valence electrons does sulfur have?

• 4

• 5

• 7

• 6

What is the formal charge of the sulfur atom in the sulfate ion?

• 0

• -1

• +1

• -2

What is the overall formal charge of the sulfate ion?

• 0

• -1

• -2

• +2