CHEMISTRY COMMUNITY

BaileyB1F

I found this definition online "Ligands are ions or neutral molecules that bond to a central metal atom or ion. Ligands act as Lewis bases (electron pair donors), and the central atom acts as a Lewis acid (electron pair acceptor). Ligands have at least one donor atom with an electron pair used ...

BaileyB1F

I hope I am answering the question correctly, but I thought an example would help. The conjugate acid is formed when a proton is added to a base. The conjugate base is formed when a proton is removed from an acid. So, NH3 + H20 --><-- NH4+ + HO- is the example. NH3 is the base, and any acid in water...

BaileyB1F

4. A sodium hydroxide solution has [HO-] = 3.50 x 10-3 M. What is its pH?
I'm still a bit confused on solving for pH and I was wondering if someone could walk through and explain the steps of this example. Thank you in advance.

BaileyB1F

H2O and NH3 are amphoteric and are not metalloids.

BaileyB1F

I'm not sure if this is correct or fully answers your question, but I found this online. "The d orbitals can point their lobes between the axes: the dxy has lobes in the xy plane but between the x and y axes; the dyz is in the yz plane with lobes between the y and z axes; the dxz is in the xz p...

BaileyB1F

I would try to first draw out the Lewis structure to see how many lone pairs there are. The three nitrogens in HN(CH2CH2NH2)2 each have a lone pair, so they have the ability to bind to a metal center. I hope that helps.

BaileyB1F

I'm having trouble with finding the oxidation state of transition metals and was hoping someone could explain this example to me: Ag and (NH3)2
Thank you

BaileyB1F

According to this website https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Book%3A_The_Basics_of_GOB_Chemistry_(Ball_et_al.)/10%3A_Acids_and_Bases/10.02%3A_Brnsted-Lowry_Definition_of_Acids_and_Bases "Because the water molecule donates a hydrogen ion to the ammonia, it is the Brøn...

BaileyB1F

I don't have any fast way to memorize it, but I like to look at it like a staircase where everything is a metal on the left of there periodic table (except for hydrogen) and then the staircase separates the metals from the non-metals. The staircase is all of the metalloids and to memorize it, you co...

BaileyB1F

For the example CuCl5, Cu is the transmission metal and is also a Lewis acid while the Cl is a Lewis base. Is the transmission metal always going to be the Lewis acid and accept the electron from the atom it bonds with? Is there a specific way to tell?

BaileyB1F

The terminal atom gives the needed amount of electrons for stability. Cl donates its electrons to stay sp3 and can't hybridize as a result. I think this is correct, but I would get a second opinion, hope this helps.

BaileyB1F

Why are lone pair and lone pair bonds stronger bonds than bonding electrons and bonding electrons?

BaileyB1F

According to Sapling, delocalized pi bonds occur when pi orbitals extends over more than two atoms. In terms of Lewis structures, this occurs with resonance structures involving double and triple bonds. O3 and CO3- have resonance structures, but H2O and HCN don't have a second resonance structure th...

BaileyB1F

One question from a practice problem for identifying the shape and bond angles was PCl5. The answer was that the shape was trigonal bipyramidal and the bond angles included 90, 120, and 180 degrees. I understand where the 90 and 180 degrees comes from, but I have no clue where that 120 came from. Th...

BaileyB1F

Hi, I was wondering if anyone had any tips for remembering the molecular geometry (trigonal pyramidal, linear, t-shaped, octahedral, etc.). Are there any acronyms or chart that could be helpful when identifying the molecular geometry? Thank you.

BaileyB1F

According to this website, https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Book%3A_Introduction_to_Inorganic_Chemistry/02%3A_Molecular_Orbital_Theory/2.04%3A_σ%2C_π%2C_and_δ_orbitals, d orbitals can form sigma bonds. I'm not sure about the rest of your question, but the website might hav...

BaileyB1F

Hi, I don't have any ways to memorize it yet myself, but I found this cool Youtube video that breaks it down and uses the an example of remembering it like a BLT sandwich. I hope that helps!

https://www.youtube.com/watch?v=GnXSGR- ... =emb_title

BaileyB1F

Yes, I think we do have to consider the most stable structure. Like in the lecture video on Wednesday from this week, try thinking of removing the individual atoms and seeing how stable they would be if you removed one from the side or one from the top (seesaw example). The more stable structure wil...

BaileyB1F

I'm confused about the reasoning behind the answers for these problems. 2A.9 asks about the M2+ ions that have the following ground-state [Ar]3d^7 and the answer is cobalt 2+ but when 2A.11 asks about M3+ ions that have the ground-state [Ar] 3d^6 the answer is also cobalt. Can someone please explain...

BaileyB1F

Online it says the angle measurement for the 'seesaw' molecular shape is between 90 and 120 degrees but I'm not sure about the second question. I think it might not depend on the exact atoms in the molecule since its more about the shape, but I'm not sure that is correct. I hope that helps!

BaileyB1F

I found this video on YouTube that shows how to draw the resonance structure for H2SO3. I hope this helps
https://www.youtube.com/watch?v=zJofo4QDrJM

BaileyB1F

How does Schrodinger's equation relate to orbitals?
Someone explained this to me before in a tutoring session, but I still don't understand it.

BaileyB1F

For the first part of your question, a dipole moment is just the separation of charge between atoms in a bond (ionic or covalent). An example would be H20 where the hydrogens have a net positive charge separate from the oxygen net negative charge. The dipole moment vectors are towards the oxygen bec...

BaileyB1F

Bond length increases down a group because the atomic radius increases.

BaileyB1F

To check on the periodic table, you have to look at the trend for bonding. Bond length increases down a group and decreases across the period.I hope that helps

BaileyB1F

An example to help understand is FeCl3 + Cl-. The Cl- is a base because it is going to donate its electron to FeCl3, making FeCl3 the base because it accepts the electron.

BaileyB1F

For this class, are we going to go over the Arrhenius acids and bases or are we only reviewing Lewis and Bronsted-Lowry acids and bases definition? Is there a major difference between the three of them that we will see in classwork problems?

BaileyB1F

I didn't do well either. To make myself feel better, I talk to my friends and family about it to see what they think or if they had similar experiences. Just hearing them talk about their struggles with midterms or classes helps me to not feel so alone about my performance on the midterm. My advice ...

BaileyB1F

This image helps to clarify the ionization and electronegativity. It's the lowest at the lower left of the periodic table (Cs) and it increases to the upper right at the highest level (F). Hope that helps. https://www.google.com/url?sa=i&url=https%3A%2F%2Frevisionscience.com%2Fa2-level-level-rev...

BaileyB1F

This response does not fully answer your question, but I found this website that describes the covalent and ionic bond relationship and a bit on polarity that might help. https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Supplemental_Modules_(Organic_Chemistry)/Fundamentals/Ionic_and_Covalen...

BaileyB1F

This question may also be something that Professor Lavelle already said or something that I should already know, but I was wondering why the transition metals in the middle of the periodic table don't have any tabled number of valence electrons like how we can tell the valence electrons of the other...

BaileyB1F

I'm not sure about lecture or discussion, but for my other classes they are not having discussions on Wednesday, but they still want us to attend another section during the week to complete our work.

BaileyB1F

https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.pngwing.com%2Fen%2Ffree-png-sgwyq&psig=AOvVaw3hcjqpisl69J_VY-bGwIdR&ust=1604205237071000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCNC8wrGA3uwCFQAAAAAdAAAAABAD This image shows the orbital diagram. This just helps to visually ...

BaileyB1F

A scientist plans on using the ejected photoelectrons in future electron diffraction experiments. For one such study, she needs the wavelength of the ejected photoelectron to be approximately 9 Angstrom (10 Angstrom=1 nm). If she irradiates the metal with 325 nm light, which of the three metals shou...

BaileyB1F

An electron ejected from zinc has a velocity 4.0x10^6 m/s. If 9.83x10^-19J of energy are required to remove an electron from a zinc atom, what was the frequency of light incident on the atom?

I got this problem from a study partner and I am having trouble on the steps of solving this problem.

BaileyB1F

For this problem, you have to set up the equation to solve for Ephoton by plugging in (6.626x10^-34)/[(9.11x10^-31)(2.5x10^-6)]. Then plug the answer (290.933) into the kinetic energy relationship (1/2)(9.11x10^-31)(290.933)^2 and you should get 3.86 x 10^-26. This is how you find the E electron (wh...

BaileyB1F

An example of an ionic bond is NaCl (sodium chloride), sodium loses an electron because that electron is in the outermost shell making it Na+ and this means chlorine takes that electron making it Cl-. An example of a covalent bond is H2O (water), oxygen and hydrogen share their electrons.

BaileyB1F

Determine the de Broglie wavelength (in nm) associated with a neutron traveling at a speed of 5.0 × 10 3 m/s. The mass of a neutron is 1.67 × 10 –24 g.
When I did this problem, I 7.94 x 10^-14, but it wasn't the right answer and I'm not sure where I went wrong.

BaileyB1F

With word problems, I like to underline what it states so I know what's missing from the equation and remember to not juts underline the numbers, but also the units because it might ask you to convert from one unit to another.

BaileyB1F

Another way to think about it is like a set of stairs. It takes more energy to climb form the first floor to the sixth floor than from the fifth floor to the sixth floor. For both cases, going up the stairs requires energy (just remember that going down the stairs, from n=6 to n=1, releases energy),...

BaileyB1F

I'm not sure if this is right, but another student from this class said on this discussion forum that, "h/4pi is an experimentally determined constant. Basically, it exists to show that there is a limit to the certainty to which you can know the position and the momentum of the particle simulta...

BaileyB1F

I heard the same from my TA about only needing one camera, and they also said some students put the external camera on a stack of books or even tape their phones to a spatula to hold it up (just a tip).

BaileyB1F

It's not on the midterm (just worry about it if you take Physics).

BaileyB1F

A trick I use to retain information is flashcards that go over definitions and equations. I also used colored pens to emphasize key terms or things that are important to remember. For organizing everything in your notebook, I say using colored sticky notes to distinguish which section or unit we're ...

BaileyB1F

I work focus on understanding the material throughout the week and then on the weekend I work on practice problems.

BaileyB1F

If we are given the constants sheet, are we also going to be given a conversion sheet for cm to m, or do we just need to already know how to do those?

BaileyB1F

A 2.00 g sample of ammonia is mixed with 4.00 g of oxygen. Which is the limiting reactant and how much excess reactant remains after the reaction has stopped?
The Balanced Equation 4NH3 + 5O2 --> 4NO + 6H2O.
What do we do after calculating the moles of the reactants?

BaileyB1F

Same, my TA is just giving practice quizzes (not graded) and told us to download Respondus (which we'll need for the Midterms). I downloaded it, but I have no clue where it went on my computer, I can't find it.

BaileyB1F

Can someone please explain number 31 from the Photoelectric Effect assessment? I don't know the steps to completing this problem. This and the following question relates to the same metal used in a series of photoelectric experiments. A. If 3.607 x 10-19 J is required to remove an electron with zero...

BaileyB1F

And remember to check your myucla or ccle to see your grade when you complete the homework assignment. It might take a few minutes to load, but it's just helpful to keep track of assignments.

BaileyB1F

I try to take a couple deep breaths, close my eyes and tell myself some words of encouragement (You got this, try your best, take your time), and removing anything that could distract me.

BaileyB1F

I like to pretend there's an arrow going through the zeros on both sides of the number. So for 0.12345 there would be 5 significant figures because the present arrow goes straight through the zero and once it hits a number that's not zero (in this case it would hit the 1), then we start counting. Fo...

BaileyB1F

I would love that too! Would we have multiple sessions so everyone has a chance to attend (like some during the week and some on the weekends)?

BaileyB1F

Hi, is there a deadline for when we have do download Respondus? And was this on the class website somewhere, or in the syllabus?
And I don't think we have a quiz every week, most likely just the 2 midterms and the final, but I would want to double check with a TA or Dr. Lavelle first.

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