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So first and foremost, I would recommend this short workbook/text by Alan Vincent as a how-to on group theory applications, specifically in handling these types of things. It can be a bit of tedium in the beginning, but it's a nice tool to walk you through the whole shebang. Anyways, I'll try to help you out with your C4v conundrum

The Γirr you have is nearly correct, but you double counted E. The correct irreducible form is 2A1 + B1 + E; the E is doubly degenerate and is only counted once, giving you a total of 3 IR active vibrations. When I use the reduction formula, I like to copy the components of the character table that I will need to use in this format.

​

|C4v|1E|2C4|1C2|2σv|2σd|
|:-|:-|:-|:-|:-|:-|
|Γirr|5|1|1|3|1|
|A1|1|1|1|1|1|
|B1|1|-1|1|1|-1|
|E|2|0|-2|0|0|

We can then use the reduction formula to find how many of each representation there are in the final irreducible form.

​

nE = (1/h)*Σ(Xi*Xr*N)

Where nE is the number of E elements in the irreducible representation, h is the order of the group i.e. the total number of operations, Xi and Xr are the respective numbers in a column for the irreducible and reducible form, respectively, and N is the number of operations in the class.

So for nE, we would have = (1/8)[(1*5*2) + (2*1*0) + (1*1*(-2)) + (2*3*0) + (2*1*0)] = (1/8)[10 + 0 + -2 + 0] = 1

You got the rest correct, so now you should see that there are indeed 3 IR active modes.

I'd recommend finding yourself two nice textbooks, and working through one methodically while referencing the second during times when the first doesn’t sufficiently explain things. Also, when studying the text, I would recommend solving as many of the “in-chapter” and “end of chapter” problems as you possibly can. You’ll be far more likely to understand the material if you have to apply the requisite knowledge, and it’s pretty established that long term recall will be enhanced by application of material (see the testing effect if curious--Roeidger and Karpicke’s studies were well done).


In fact, regardless of how you are initially presented with the material (be it Khan lectures, textbooks, guides online, people’s answers to your questions, etc.), the bulk of your understanding will likely come from working out problems yourself. This effect can not be overstated, and regardless of how you decide to engage the material, I cannot stress the importance of applying the material.


Assuming you follow the textbook plan, if you find a concept or problem that you just cannot comprehend, look to online resources for aid. Some examples include Khan Academy, MIT Open Courses, and of course, r/chemhelp or r/homeworkhelp.


If you absolutely need some direction and find that a textbook isn’t cutting it, then the MIT series has a number of explicit instructions and lectures to steer you along. If you can catch them when they’re available, Coursera has some courses as well, with actual feedback systems that would likely prove useful.


For book recommendations, I’d check out this thread: http://www.reddit.com/r/chemistry/comments/1xzi9t/general_chemistry_book_recommendations/ There seems to be a good discussion there with lots of options. I personally used Chemistry: the Central Science, but it’s worth mentioning that the math used is pretty low level and isn’t representative of further chemistry study. Still, the concepts are explained fairly well. A note: textbooks can be found for much, much cheaper than is initially seen on listings. Used copies of older textbooks often go for almost nothing. You can even sometimes find PDFs of books, but the legality of that is questionable (even if they’re way easier to navigate and manipulate).


Still, your best course of action likely depends on your individual learning style, so take these suggestions with a grain of salt.

Well, it is a combination of organic chemistry (questions IV,V and VI) and inorganic chemistry (II). Question I is a basic chemistry question.

Question III is maybe inorganic, but could be thermodynamic as well. It depends on where you get the question. I have gotten similar questions in courses about thermodynamics and inorganic chemistry.

I'm not sure what basic books could be useful for you. For my bachelor I use the books organic chemistry and Physical chemistry. These books are quite advanced, I don't know if it helps you in anyway. But this is at least a start.

Sorry, couldn't find a book for inorganic chemistry. (don't know the writer and I can't get to my books unfortunately)

Good luck with learning chemistry!

If you can get to a library, the book Culinary reactions is a fabulous layman-level book about food chemistry.

One VERY easy concept is the use of baking powder in food! This should be a good place to start

You'll end up with water and a solution of magnesium ions and phosphate ions. Whether the phosphate has any hydrogen left depends on how much hydroxide you put in. If you want magnesium phosphate, Mg3(PO4)2, you'll need to do the math to get the molar ratios right.

It's just an acid-base reaction, it will be moderately exothermic, but assuming you don't have really concentrated acid you should be all right. If you're worried wear gloves and safety goggles and mix it slowly.

Edit- I found a bottle of food-grade phosphoric acid on amazon, it says 85% in water. That's concentrated enough to be dangerous, I hope you have proper protective equipment and know what you're doing. :)

Also found a bottle of magnesium oxide powder on Amazon which would work as well as hydroxide. Again though, it'll be an exothermic reaction and there may be spattering. You might find a cheaper source of MgO or Mg(OH)2 elsewhere, but that was the cheapest food-grade I found with a cursory search.

Those.... don't look like powder funnels. The "drip tip" is the red flag; none of those are going to have particularly wide stems and the long stem is just going to get clogged with powder.

If you're on a budget I'd look for a plastic funnel with a stem OD <24 mm like this one or this one. If you're willing to fork over a little more cash and get a glass one there are nice 24/40 joint funnels like this small one or this huge one.

Standard solutions are prepared in their approximate concentrations and are then standardised against recognised primary standards.

The primary standards are all very pure chemicals that can be further purified by drying in an oven and cooling down in a vacuum desiccator over phosphorus pentoxide.

Primary standards for acids, alkalis and oxidising agents are anhydrous sodium carbonate, potassium hydrogen phthalate anf potassium iodate. In industry you use these so frequently that you get to know their molecular weights by heart.

Once you have standardised solutions of acid, alkali and sodium thiosulfate you use these to standardise other working solutions, so that you have a hierarchy of standards, with the primary standards being the most reliable.

Edit: reference Vogel's Textbook of Quantitative Chemical Analysis, the bible when I was educated.

I highly recommend this book:

https://www.amazon.com/Symmetry-Spectroscopy-Introduction-Vibrational-Electronic/dp/048666144X

My inorganic professor recommended it when I took the course and it was a great investment.

The information your gf needs appears to be on Amazon's website. Check out the "Look Inside" feature.

Best of luck in her studies!

The reaction that is happening is

Zn + 2 HNO3 -> Zn(NO3)2 + H2

Zinc + nitric acid produces zinc nitrate and hydrogen gas

So as your bath is being exhausted, the HNO3 is being used up. Eventually it'll stop because the HNO3 is all gone. What you could get is some pH paper. That will tell you how acidic the solution is. A fresh batch should have a pH around 0-1. As it reacts it'll get closer to a pH of 7. For your bath, it'll never get above 7 since that is a basic solution.

The reaction might start slowing down once it's above a pH of 5-6, but you'll have to do a little monitoring to see what's best.

"Organic chemistry is learned only with a pencil and paper"

-My orgo professor

Best advice I got, I say it all the time as a chemistry teacher, repetition, writing things over and over, is the only way to really get it, at least for me. I would take a ream of paper from the printers in the library and sit at a desk and write structures and reactions until I got them.

Also I really liked these books as a supplement

Essentially what this product does:
https://www.amazon.com/Acid-Phosphate-8-oz-Bottle/dp/B008K76J6E/ref=sr_1_1_a_it?ie=UTF8&qid=1486960742&sr=8-1&keywords=acid+phosphate

I'd buy it but its pricey and I am pretty far from the states so there's just no way I can get it. The second picture shows what it has, so I'm trying to replicate it. I've got all the other phosphates, I'm just missing the magnesium. Any help would be appreciated.

There’s a hint of the effect present in isotopic lifetimes in this chart. The same factors that determine the abundance of an isotope are at play when these isotopes are created in supernovae.

There’s a very nice treatment of relative stability of nuclides in this excerpt (pp. 20-25) of Basic Bethe.

I've yet to have to use it, but I've hear this book Organic Chemistry As a Second Language, is amazing

I highly recommend this book: https://www.amazon.com/gp/product/0131008455/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 It really saved me when I took physical chemistry after only having taken Calc 1.

You might want to pick up a chemistry model set -- it really helps people who have a hard time visualizing 3D structures! Your student bookstore might have them, but if they are out, this is what you're looking for :)

http://www.amazon.com/Organic-Chemistry-Molecular-Model-pieces/dp/B002MNSC9Y

This is a really great book. Not sure how "undergraduate" it is. But I'm not sure just how undergraduate chemical kinetics, as subject all to its own, is either. The mathematics is not the simplest.

But this book will cover any topic. It's very thorough.

I'd also recommend McQuarrie's PChem book. It has a very clear section on kinetics. And it's my favorite PChem book, but only just nudging out Atkins.

Do a lot of problems. Doing problems helps more than studying your notes.

Also, fuck the textbook they assign. Get this one, it's by far the best pchem book. It does an excellent job of teaching the math and the theory.

http://www.amazon.com/Physical-Chemistry-A-Molecular-Approach/dp/0935702997/ref=sr_1_1?ie=UTF8&qid=1375808822&sr=8-1&keywords=physical+chemistry+a+molecular+approach

Finally, learn to derive the equations. Even if you aren't tested on derivations, it really helps you grok the material and how all the pieces relate.

Well I didn't intend to use it strictly as a powder funnel if at all, so my question remains, what size would the the most similar to this one, mentioned previously?