CHEMISTRY COMMUNITY

Navi Sidhu 1F

First functional groups, then double/triple bonds and then substituents. So you're correct. Dr. Lavelle has stated he wouldn't give us 2 functional groups. See the forum below for verification. Check out this long thread for more info: https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=83&t=200...

Navi Sidhu 1F

Torsional Strain: When rotating a molecule around a bond, the torsional strain is the repulsion caused by the electrons in between different groups when they pass by each other. Torsional strain can be lessened by rotating a molecule around a bond. Steric Strain: Strain caused by the electrons in be...

Navi Sidhu 1F

When a molecule is able to rotate around a sigma bond, there is bound to be different levels of torsional strain that vary with the placements of the substituents relative to each other. This leads to different conformations of molecules (such as staggered or eclipsed) with different energy levels, ...

Navi Sidhu 1F

The minimum energy requirement that must be met for a chemical reaction to occur is called the activation energy, Ea. The activation energy (Ea), labeled ΔG‡ is the energy difference between the reactants and the activated complex, also known as transition state. In a chemical reaction, the transiti...

Navi Sidhu 1F

The y-axis is the fraction of molecules, so if the peak of the high temperature curve is lower that means that there are less molecules at that certain level of kinetic energy. As the graph shows, the further right you go on the x-axis, the greater the kinetic energy. I assume that fraction of molec...

Navi Sidhu 1F

If you have non metal/ion pair undergoes redox, most of the time you need solid electrode to supply e-. These electrodes can be on either ends of the cell diagram.

Navi Sidhu 1F

This forum post may answer your question: https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=140&t=5207&sid=8a327eb0369821b49facabd48e3cc546

Navi Sidhu 1F

A question like this was asked in our last quiz. Basically what it comes down to is: Number of atoms/Number of unique positions of the atoms (degeneracy) Rigidity of bonds For example, which has larger molar entropy, CO or N 2 ? t=0K, and both molecules have the same geometry. Since the number of at...

Navi Sidhu 1F

This was a response by Chemmod a couple of years ago: This reaction is the opposite of Problem 13.11d so to make the comparison easier I will flip this reaction (this does not change the chemistry). In that problem you are given the cell diagram to help in the selection and you then solve for the f...

Navi Sidhu 1F

Prof Lavelle typically requires us to round at the end of a calculation.

Navi Sidhu 1F

The Van't Hoff Equation allows us to see how temperature changes can affect K. Here is a breakdown of the components of the equation: K 1 = initial equilibrium constant K 2 = final equilibrium constant \Delta H ^{_{\circ }} = standard formation of enthalpy R= Gas constant T 1 = initial temperature T...

Navi Sidhu 1F

I like to think of these problems like they have a moveable piston; one that moves up or down while responding to volume changes inside the beaker/cylinder in order to make the internal and external pressure equal, as it is in a open system. For example, Gas A (3 L) and Gas B (2 L) react to form 6 L...

Navi Sidhu 1F

The equations on the back-side of the laminated periodic table you received with your course reader are all the possible equations and constants Prof Lavelle will supply us during an exam. In Chem14A, he picked the formulas that were relevant to us as the time and attached them to the test; I'm assu...

Navi Sidhu 1F

1. Login 2. On the top right hand of your screen, click on your current username . (it has a upside-down triangle next to it; this will open three more options in a drop down box) 3. Click on User Control Panel 4. Under edit account settings , change your username 5. Enter your current password in t...

Navi Sidhu 1F

In a open system, the system is not sealed and is not insulated . In a closed system, the system is sealed but is not insulated . In a isolated system, the system is sealed and insulated . When a system is sealed, matter cannot be exchanged with its surrounding; when it's not sealed it can. When a s...

Navi Sidhu 1F

I'm assuming yes because in the course reader it is outlined how to convert between Partial Pressure (K_p) and Concentration (K). See page 133.

Navi Sidhu 1F

An atom loses an electron.

It says, "Man, I really have to keep a better ion them!"

Navi Sidhu 1F

Taken from http://study.com/academy/lesson/what-is-salt-in-chemistry-definition-formula.html because they have a clear, concise definition: In chemistry, a salt is an ionic compound which is made up of two groups of oppositely charged ions. The ion with a positive charge is called a cation, and the ...

Navi Sidhu 1F

You determine the charges on all the ligands/atoms. If the molecule is neutral (which coordination compounds by their very definition are), then the charges must equal zero; therefore, the oxidization number of the central atom will equal whatever charge makes the molecule neutral. Here is a very si...

Navi Sidhu 1F

These (credible) websites suggest that it's 90/120 degree angles. http://chem.libretexts.org/Core/Inorganic_Chemistry/Molecular_Geometry/Square_Pyramidal http://butane.chem.uiuc.edu/pshapley/GenChem2/A1/3.html http://homepage.smc.edu/scholefield_michelle/chem11/handouts/VSEPR%20Theory%20and%20the%20...

Navi Sidhu 1F

Dipole moments can cancel if the molecule is symmetrical. Example: BeF 2 . The charges are vectors so if they go in opposite directions and have the same charge, (when you add them) they will cancel. You don't really need to have knowledge of vectors, just know if it's going in opposite directions a...

Navi Sidhu 1F

We will not be tested on Sigma and Pi bonds in quiz #2. Only material from chapter 2-3.

Navi Sidhu 1F

Why did carbon marry hydrogen?
They bonded really well from the moment they met.

Navi Sidhu 1F

Here's another one from chemistry cat:

Navi Sidhu 1F

Is it still accurate/appropriate to write (for example, carbon) 1s² 2s² 2p² instead of what we learned today: 1s² 2s² 2p_x¹ 2p_y¹ ?

CHEMISTRY COMMUNITY

Search found 25 matches

Re: Priority when Naming

Re: Torisonal vs. Steric Strain

Re: Torsional Strain

Re: Activation energy [ENDORSED]

Re: Relationship between k, T, and Ea Graph

Re: Cell Diagrams [ENDORSED]

Re: When to add H+ in cell diagram?

Re: Comparing molar entropies of different molecules

Re: H2O->H+ + OH-

Re: Sig Figs

Re: Van't hoff equation

Re: open system

Re: Exam Formula Sheet

Re: Username

Re: CLOSED vs ISOLATED

Re: Chemical Equilibria

Re: Post All Chemistry Jokes Here

Re: Identifying a salt

Re: Oxidation Numbers

Re: Square Pyramidal

Re: Dipole Moments And Polarity

Re: Sigma and Pi Bonds

Re: Post All Chemistry Jokes Here

Re: Post All Chemistry Jokes Here

Orbital Question [ENDORSED]