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Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 4:00 pm
by KC Navarro_1H
What are some differences to remember between pi and sigma bonds? If I remember correctly, sigma bonds are more flexible than pi bonds, and double and triple bonds are made up of a mix of the two. What else is important to remember about them? Thank you!

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 4:04 pm
by 804991762_4A
For me, I find it useful to remember how they overlap such as that there's an axis and sigma lays along the axis, while pi is above/below the bond axis.

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 4:21 pm
by Aryana Nazem 1A
all bonds have one sigma bond, when you have two bonds there is one sigma and one pi bond, and when you have a triple bond you have your sigma and two pi bonds. I think this is an important rule to remember and to be able to distinguish

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 9:07 pm
by Anthony Mercado 1K
So, in relation to sigma and pie bonds, does each increase in bond length constrain the molecule on an increasing number of axis(s)? That is, a sigma bond just constrains it on an axis, a pi bond would not allow it to rotate, and a triple bond would mean even more constraints in molecular movement?

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 9:37 pm
by Myles Chang 1B
I think Pi bonds differ from Sigma bonds in how they affect a molecule's structure. Pi bonds prevent a molecule from rotating, namely.

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 10:30 pm
by Madeleine Farrington 1B
Anthony Mercado 1K wrote:So, in relation to sigma and pie bonds, does each increase in bond length constrain the molecule on an increasing number of axis(s)? That is, a sigma bond just constrains it on an axis, a pi bond would not allow it to rotate, and a triple bond would mean even more constraints in molecular movement?

Everything you have said sounds accurate to me other than that the bond length would be increasing. I was under the impression that a double or triple bond would be shorter than a single bond. But I agree that a sigma bond would simply constrain the atoms to an axis around which they could rotate, where as a double or triple (pi) bond would not allow for rotation.

Re: Differences Between Pi and Sigma bonds

Posted: Sun Jun 03, 2018 10:34 pm
by Surya Palavali 1D
Sigma bonds are present in all bonds, pi bonds are not.

Re: Differences Between Pi and Sigma bonds

Posted: Wed Jun 06, 2018 12:28 am
by Alicia Beebe
From my understanding, pi bonds are easier to break, so they're the "first to go." This also makes sense along with what others were saying because each bond is at least one sigma bond, sigma bonds form first and break last. But, in each bond there can only be one sigma bond, so a double bond is one sigma and one pi bond, and a triple bond is one sigma and two pi bonds.