CHEMISTRY COMMUNITY

Ashita Tanwar 3H

The "ate" is only there when it is an anion. Otherwise it is just cobalt.

Ashita Tanwar 3H

Is it possible for a coordination compound to have multiple transition metals? Or will there always only be one? If there are more, how would we name the metals?

Ashita Tanwar 3H

Can there be multiple rings around the same central atom?

Ashita Tanwar 3H

What are all the signs that indicate a molecule has dipole moments and how do you know where to draw them on the molecule?

Ashita Tanwar 3H

Also, how do you figure out if a molecule is polar if there are no lone pairs? Do you use the formal charges?

Ashita Tanwar 3H

For hybridization, do we just have to be able to figure out the hybridization of molecules based on their VSEPR structure and leave it at that? Or can we use hybridization to generate more information about the molecule?

Ashita Tanwar 3H

Bond angles will be different because the repulsion between the pairs where there is one versus two lone pairs is significant enough to have an effect on the bond angles.

Ashita Tanwar 3H

If the AXE formula is a template, does it change/become more specific when referring to a particular molecule? Or will it always be AXE?

Ashita Tanwar 3H

Do the bond angles need to be memorized as well, or is there a formula that can determine what the angles are?

Ashita Tanwar 3H

Also keep in mind that in molecules, double and triple bonds are decentralized so all the bonds in the molecule should be the same length!

Ashita Tanwar 3H

Is it possible to use VSEPR theory with atoms with more than one central atom? If it is, how do you write the VSEPR formula for molecules with more than one central atom?

Ashita Tanwar 3H

Is it possible to tell which molecules have smaller bond angles even when we're not sure exactly what the bond angles are? Like would the size of the atoms in the molecule have an effect on the bond angles, or is it just a matter of how many / what kind of electron pairs there are?

Ashita Tanwar 3H

For questions like these, are we always supposed to assume that the formal charge of the molecule is 0? Will the formal charge be provided when it is something other than 0?

Ashita Tanwar 3H

For the most part, electron affinity and ionization energy show the same trend across the periodic table. Fluorine has one of the greatest electron affinities and ionization energies, and these values decrease as you get closer to group 1/period 7. That being said, it's important to remember that el...

Ashita Tanwar 3H

For complex molecules that are radicals, how do you know which atom gets assigned the extra electron? Does it have to do with periodic trends?

Ashita Tanwar 3H

We don't know how to calculate electronegativity, and for the most part it is determined in a lab setting anyway. If the elements are close together, then the values will likely be given. Otherwise we need to use our knowledge of periodic trends to determine the least/most electronegative element :)

Ashita Tanwar 3H

Yes, there is a facebook groupchat for chem14A on Messenger! There's a link on the CO22 facebook page :)

Ashita Tanwar 3H

I'm not 100% positive about this, but it's odd that the question asked for M^2+ ions and the answers are all M^3+ ions. Maybe it was a typo?

Ashita Tanwar 3H

No, electron configurations are Week 4 material, so they should be on the midterm/final and following test. We do need to know the wave function numbers though (n,l,m) and orbitals etc. Hope this helps!

Ashita Tanwar 3H

Does this mean that the equation given in the atomic spectra module always uses the lower energy level "n" as n1, regardless of whether it is the final or initial value? For example, if an electron was dropping from n=4 to n=2, then would the equation be the same if the electron was jumpin...

Ashita Tanwar 3H

Prof. Lavelle didn't explicitly go over any particular experiments that were important to De Broglie's equation, but it's important to remember that De Broglie waves can be experimentally observed in a lab setting. Hope this helps!

Ashita Tanwar 3H

There are certain waves that are able to be detected/tested for in the lab setting and it just so happens that waves beyond 10^-18 are too small to be detected. That's why the cutoff is at 10^-18 :)

Ashita Tanwar 3H

Do objects that have no "rest mass" have mass when they are moving? Or do they just never have mass? How can the mass of an object change depending on its movement?

Ashita Tanwar 3H

One TA told me that the reason there is uncertainty when determining the position/momentum of particles is because we can't take into account both the matter properties and wavelike properties of said particle, but I also heard that the uncertainty is because "by the time we calculate momentum,...

Ashita Tanwar 3H

What does it mean when delta E turns out to be negative after calculating the energy difference between two energy levels? I'm not sure if the sign makes a difference

Ashita Tanwar 3H

The units for "E" are Joules/photon, so if we're using the equation for a situation that only involves one photon, there's no real difference. If there's more than one photon being discussed then you need to take into account that the answer is for only one photon

Ashita Tanwar 3H

Also, in class we used the equation on everyday objects like a baseball and car so it can be applied to pretty much any object that is moving, the only thing is that larger objects don't have wavelike properties that are measurable.

Ashita Tanwar 3H

Both of the values have the same number of significant figures: 3 sig figs. Adding a decimal point is tricky when it comes to sig figs!

Ashita Tanwar 3H

For questions like these, do the trailing zeroes count as sig figs? For example, do 400.00 and 400.0 have the same number of sig figs?

Ashita Tanwar 3H

No, this topic shouldn't be on our first test because it wasn't included in the assigned Appendix pages or the outline for week 1. But it wouldn't hurt to review :)

CHEMISTRY COMMUNITY

Search found 30 matches

Re: Transition Metal Names

Transition Metal

Re: chelates

Dipole

Re: Polarity

Hybridization/VSEPR

Re: Bent - Lone Pairs

Re: VSPER Formula

Re: Molecular Shape

Re: Bond Lengths

VSEPR w/ more than 1 central atom

Re: Formula for determining bond angle

Re: Identifying the element

Re: Electron Affinity vs. Ionization Energy

Re: Radicals

Re: Electronegativity

Re: Midterm study

Re: 7th Edition 2A.11

Re: Test 2 outline

Re: Rydberg Equation

Re: DeBroglie Equation and experiment

Re: Measurable wavelike properties?

Rest Mass v. Movement

Clarification on Heisenberg Equation

Negative v. Positive when calculating energy

Re: Energy of a Photon

Re: DeBroglie Equation

Re: Decimal point

Re: Sig Figs

Re: Net Ionic Equation?