Drawing the Lewis Structure for Cl2

Viewing Notes:

  • Cl2 is a green, poisonous gas. The Cl2 Lewis structure is similar to F2, Br2, and I2 since F, Br, and I are all in Group 7 and have 7 valence electrons.
  • For the Cl2 Lewis structure there are a total of 14 valence electrons available.

Transcript: OK, we're going to draw the dot structure for Chlorine gas—a poisonous green gas. This is Dr. B. And we'll start out by figuring out how many valence electrons we have for Chlorine. On the periodic table, it's in group 7 or 17, so it has 7 valence electrons; but we have two of them, so let's multiply that times two for a total of 14 valence electrons. So we're going to spread those around the atoms, fill the octets, form a chemical bond. So here's Chlorine, and another Chlorine.

Let's start by putting two valence electrons between the Chlorines. That forms the chemical bond. And then we're going to spread them around the outside atoms, trying to give each one eight. So we have 2, 4, 6, 8, 10, 12, 14. We used all 14 up. Now let's see if we have octets, eight valence electrons around each. That Chlorine has 8, and this Chlorine right here, 2, 4, 6, has 8 as well. So we've actually finished this Lewis structure for Cl2; a pretty straightforward one.

And let's just count: 2, 4, 6, 8, 10, 12, 14. So we're good there. We could also draw it as a structural formula that would look like this. These two electrons right here would be represented by a single line that shows you a pair of valence electrons, and it shows that they're bonded.

That's the Lewis structure for Cl2, Chlorine gas. This is Dr. B., and thanks for watching.