Chemistry

I think chemistry, especially inorganic chemistry to be one of the toughest sciences, even more so than mathematics or biology. In chemistry you have to remember an incredible amount of information. Whereas with math, you only need to learn a few principles for any one problem. What are your views?

Can somone tell me the easy/ low cost method of getting 98% HNO3 from 60-70% HNO3 solution.?

Does anyone know of a way to quantitatively express the amount of vibronic-coupling that occurs in a given molecule? I know that vibronic-coupling allows some transitions to occur that are traditionally Laporte [parity] forbidden; and I know how all this works qualitatively. I imagine this has something to do with UV-vis spec. Perhaps there are some "epsilon" values that are typical of these types of excitations? This is not homework, but extracurricular (curiosity killed the cat!). Any insight would be appreciated.

Hello guys, Ok I know surfactant has a polar and non polar group and then go to the surface and break the bonds. My question is the surfactant would still arrange itself like this picture, meaning surfactant and surfactant would have strong bonds at the surface. So how does this reduce surface tension, is surfactant surfactant bond less strong than eg water water bond here? Thanks

So my freshman year at college is wrapping up, and that means we are doing all those oddball chapters in chemistry, including nuclear chemistry. This is a subject I am very interested in, but I have some general questions about the field. There seems to be a general feeling that this type of science is in the realm of physics. Yet it is taught in chemistry classes as well. Is there a difference between a nuclear chemist and a nuclear physicist? Would getting a degree in chemistry not prepare me for this field compared to getting a degree in physics?

describe the preparation of 500ml of 4.75% w/v aqueous ethanol (mm=46.1 g/mol)

I'm looking for a list that would give most to all of naturally occuring gas and liquid molecules: [ce]H2O[/ce], [ce]O2[/ce], [ce]CO2[/ce], [ce]N2[/ce], etc.. I am looking for molecules that occur naturally in one atmosphere of pressure in a relatively temperate enviroment. If anyone has any links to a site or sites that would have something like this it would be greatly appreciated.

How do scientists know which catalyst to use in different reactions? For example, how do scientists know to use acid for esterification?

How would you be able to predict how many bonds a substance might have? Ex. If you burn Iron (Fe) in Oxygen (O2), what are the possible compounds? I know for Iron these are possible. Fe2O3, FeO, and Fe3O4. But how would you predict it if you burned Zirconium (Zr) or Tungsten (W) which have different oxidation numbers?

I can accept the explanation for both phenomena independently. 4s is lower in energy than 3d so it fills first. And 3d penetrates better than 4s so 4s leaves first. Accepting them at the same time does not seem possible. If 4s is lower in energy then how can 3d penetrate better? If one is true then it seems to make the other not make sense! If electron filling is based on energy levels, then how can something be lower than another shell when filling, but higher in energy when losing?

I don't understand the bonding of the transitional metals. It seems that the non-metals, the alkali, and the alkaline earth elements have some sort of predictable bonding pattern. I just can't figure out how to predict bonding with the transition metals. Can anyone help?

Just the other day I was talking about chemistry and some guy said a cool experiment was to mix fertilizer, soap, and gas together then lite it. Now this guy really doesn't like me much, and I don't like him very much. So I don't want to try it until I know for sure what it does. Any ideas? Thanks.

I was told that ninhydrin could react with secondary amine to form a colored complex of iminium salt. However, in an experiment I treat N-acetylglucosamine with ninhydrin, it gave negative result. N-acetylglucosamine contains a secondary amino group, but why it gave negative result? But ninhydrin gives colored complex with proline, which is also a secondary amine... Is it just different iminium salts have different absorption spectrum?

Can the following reactions be reversed, and if so, how? 2 Ca2SiO4 + 5 H2O---> 3 CaO.2SiO2.4H2O + Ca(OH)2 + 58.6 kJ Tricalcium silicate + Water--->Calcium silicate hydrate+Calcium hydroxide + heat 2 Ca3SiO5 + 7 H2O ---> 3 CaO.2SiO2.4H2O + 3 Ca(OH)2 + 173.6kJ

I have heard this commented on before, that we do not have much uranium left in the world. This topic may already have a thread. I tried searching for it to no avail, so I apologize in advance if it does. Anyway could someone elaborate on this?

Hi! I need to mix some high molar NaOH in a container which can be heated to 105C and stirred for between 3-5 hours. Does anyone have any suggestions on what sort of container I should use? I have heard stainless steel mentioned, but I was hoping for something cheaper. Suggestions? Thanks!!!

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I was wondering where I might be able to order/buy chemicals from. Preferibly from a chemistry catalog, I want to get pure chemicals, not like lye from wal-mart. I would like to get the appropriote licences too, which is why I'm not so keen on Ebay, online stores, ect. Thanks

If you have a small pot of boiling water and you add some cold water to it does the motion of the boiling water keep the cooler water at a boundary for a bit of time, or does the cool water instantly sink in and mingle with all of the water?

atoms form bonds with each other to be stable, right? If so, how come substances like hydrocarbon are so volatile? Souldn't it be stable?

Given the specific rotation of L- Alanine = + 1.8° ( 25° C), calculate the optical rotation (observed) of a 1.10 M solution of Alanine in water at 25° C in a 25cm polarimeter tube. Show all calculations I know the formula is Specific Rotation = observed rotation (deg) × 100 / Optical path length (dm) × concentration (g/100ml) I think I found that the concentration is 0.097999 g/mL and the optical path length is 2.5 dm but I'm little bit confused and I was absent on the class that was talking about this because I had a fever. can anyone help me?

An experimental alloy contained by copper and tantalum of the alloy was dissolved and analyzed gravimetrically. a) the copper was precipitated and weighed as CuO, a mass of 0.1739g was obtained. Calculate the %w/w Cu in the alloy. b) the tantalum was precipitated and weighed as Ta2O5, a mass 0.4748g was obtained. calculate the %w/w Ta in the alloy.

Can we tell if a substance is going to produce a lot of energy (when go through a chemical reaction) by looking at their electron configuration?

For example: gasoline Is it because of their electron configuration? If so, how does it plays in the role of producing vast amount of energy?