Jaden's Workshop Week 6/7 - Midterm #2 Review (UPDATED ANSWER KEY AS OF 7:50PM) Topic is endorsed

[Chem_Mod]

Hi everyone,

Super glad to get back to our sessions! The last time I had a session was also for your midterm as I was away last week. Hope that session was able to clarify some of y'alls content gaps and hopefully I'll be able to do that again with this session. Like last time, try to arrive early as spots are limited with people having to sit once space runs out. We'll be covering thinks like molecular geometries, lewis structures, polarizability/polarizing power, and intermolecular forces.

Hope to see y'all at De Neve Sycamore tomorrow from 11am-1pm!

-Jaden

[Chem_Mod]

Hello hello everyone!

Delayed on giving an answer key to give everyone a chance to do the worksheet.

An answer key will be posted later tonight

[Chem_Mod]

Hello hello!

Here's the answer key to my worksheet. There's some good stuff on this worksheet such as resonance structures and how it can affect polarity!

Some clarifying remarks as I was asked really good questions in my section.

Why is CO2 a Lewis Acid?
CO2 is considered a Lewis Acid because of the partial positive charge that results from the dipole moment when O2- ions bond with carbon. These yields two C-O double bonds. However, because the carbon is partially positive it can accept electrons IF arrow pushing is used. When I say arrow pushing, I mean carbon "can" push electrons from the double bond and push it back onto the oxygen giving a C-O single bond. From here, the carbon can accept another pair of electrons via a coordinate covalent bond for example!

Hope this worksheet and my clarifying statement helps!

[Kate Anderson-Strain 2I]

Hello!

For Question 3 Part C why is it Rb+, Li+, Ca2+, Mg2+? I thought it was Rb+, Ca2+, Mg2+, Li+. Rb+ has the largest radius and lowest charge (+1) so it has the least polarizing power. Then Ca2+ because its relatively large (but smaller than Rb+) and has a larger charge (2+). Then Mg2+ because its relatively smaller than Ca2+ and has a larger charge (2+). Then Li+ because its the smallest and has a high charge density.

Thank you!

[Chem_Mod]

Hello!

For Question 3 Part C why is it Rb+, Li+, Ca2+, Mg2+? I thought it was Rb+, Ca2+, Mg2+, Li+. Rb+ has the largest radius and lowest charge (+1) so it has the least polarizing power. Then Ca2+ because its relatively large (but smaller than Rb+) and has a larger charge (2+). Then Mg2+ because its relatively smaller than Ca2+ and has a larger charge (2+). Then Li+ because its the smallest and has a high charge density.

Thank you!

Hi Kate,

Thank you for pointing this out. Because we're comparing different columns with the elements being far away from another it's hard to say what's larger. Dr. Lavelle won't give a problem like this where atoms are far apart. You're correct in that Mg2+ should be after Rb+. However, Mg2+ is the smallest and you can only deduce this from additional information. Again, this isn't clear unless you search up information, which makes this size comparison unfair to put on an exam. It should be very clear on the exam which is larger or smaller.



-Jaden

[Sahra Sutaria]

Hi!
In problem 8a, why would dipole-dipole not be a force exhibited. I always assumed that where a hydrogen bond could occur there was a dipole-dipole moment.

Thanks,
Sahra