Exceptions

Moderators: Chem_Mod, Chem_Admin

Norah Gidanian 3D
Posts: 128
Joined: Wed Sep 30, 2020 9:49 pm
Been upvoted: 1 time

Exceptions

Postby Norah Gidanian 3D » Fri Nov 06, 2020 10:00 am

Do we just need to memorize which atoms are exceptions or is there a way to tell? Also what are all of the exceptions we should have memorized.

Kayla Booker 1F
Posts: 86
Joined: Wed Sep 30, 2020 9:43 pm

Re: Exceptions

Postby Kayla Booker 1F » Fri Nov 06, 2020 10:11 am

I’m not sure about how many exceptions there are, the ones I know of are B, Al, and Be. The way to tell that they are exceptions is if there is no way for the middle atom to create and octet

Charlotte Adams 1A
Posts: 159
Joined: Wed Sep 30, 2020 9:46 pm
Been upvoted: 1 time

Re: Exceptions

Postby Charlotte Adams 1A » Fri Nov 06, 2020 10:57 am

The books says there are several types of exceptions:
- a molecule might have an odd number of electrons so octet formations is numerically impossible (radicals)
- atoms of certain elements might be able to accommodate more than eight electrons in their valence shell (expanded valence shell)
-an atom might form compounds with incomplete octets (incomplete octet)

hope this helps!

Chelsea_Guzman_3C
Posts: 86
Joined: Wed Sep 30, 2020 10:06 pm
Been upvoted: 2 times

Re: Exceptions

Postby Chelsea_Guzman_3C » Fri Nov 06, 2020 11:44 am

I think being able to recognize or understand what makes an atom an exception is best. But knowing some like Be and B could be just as helpful, but I doubt memorizing all of them is necessary.

605291562
Posts: 86
Joined: Wed Sep 30, 2020 10:07 pm

Re: Exceptions

Postby 605291562 » Sun Nov 08, 2020 4:24 pm

I think being able to recognize them is more important then memorizing them, based on how this class has worked so far I feel like it has been more about application than memorization. Also I think if it was something to memorize it would have been listed on the outline.

IshanModiDis2L
Posts: 84
Joined: Wed Sep 30, 2020 9:49 pm

Re: Exceptions

Postby IshanModiDis2L » Sun Nov 08, 2020 5:55 pm

I would agree with what was said above, the way to tell that they are exceptions is that if there is no way for the middle atom to achieve a full octet. You do not need to memorize all of them, I would say its more favorable if you recognize them instead.

Heather Szeszulski 1I
Posts: 59
Joined: Wed Sep 30, 2020 9:55 pm

Re: Exceptions

Postby Heather Szeszulski 1I » Sun Nov 08, 2020 6:05 pm

Chelsea_Guzman_1B wrote:I think being able to recognize or understand what makes an atom an exception is best. But knowing some like Be and B could be just as helpful, but I doubt memorizing all of them is necessary.

What is the best thing to study to be able to understand the exceptions?

Ayesha Aslam-Mir 3C
Posts: 112
Joined: Wed Sep 30, 2020 9:43 pm

Re: Exceptions

Postby Ayesha Aslam-Mir 3C » Sun Nov 08, 2020 11:39 pm

Is there a way to use either periodic table trends (or indications or orbitals) or just the character of an element to determine of it's an exception to the rule?

Ayesha Aslam-Mir 3C
Posts: 112
Joined: Wed Sep 30, 2020 9:43 pm

Re: Exceptions

Postby Ayesha Aslam-Mir 3C » Sun Nov 08, 2020 11:40 pm

IshanModiDis2L wrote:I would agree with what was said above, the way to tell that they are exceptions is that if there is no way for the middle atom to achieve a full octet. You do not need to memorize all of them, I would say its more favorable if you recognize them instead.


Is this a way to tell for individual atoms with the same concept?

Queena Chu 3E
Posts: 81
Joined: Wed Sep 30, 2020 10:09 pm

Re: Exceptions

Postby Queena Chu 3E » Sun Nov 08, 2020 11:53 pm

I think it's best to be able to recognize what exceptions there are.
Some excpetions include:
Molecules, such as NO, with an odd number of electrons
Molecules in which one or more atoms possess more than eight electrons, such as SF6
Molecules such as BCl3, in which one or more atoms possess less than eight electrons


Return to “Octet Exceptions”

Who is online

Users browsing this forum: No registered users and 1 guest