hermanntrude

willing, but not able, in my case. I don't know the relative solubilities of Fe2O3 and Al2O3, although if you look up their Ksp values, that'd help you calculate which one will precipitate first and how much will be left when the second one starts to precipitate. Look up "solubility product constant" on wikipedia and see what you get. if it seems to be something you want to persue, let me know and i'll try to help you along the way. i should warn you, though, sometimes it's not feasible to separate mixtures like this.

I suspect (although i'm not sure) that your ideas about parts and 2 are correct and probably at least part of the answer. Part 3 would probably be helped if you looked up the "common ion effect"

well if it can't, the hydrocarbon before the first solid one would be a liquid with a higher viscosity than water.

no problem. Just making you aware

here's a useful link. I downloaded the software used to draw these orbitals and it really helped me understand them better. I even made the four sp3 hybrid orbitals

If you havent covered free energy yet, you will if you do first year degree-level chemistry courses.

for example, hydrocarbon chains twenty or so carbons long are waxes. ie they are solids, whereas water, with its hydogen bonds is still a liquid. london dispersion forces CAN be stronger than hydrogen bonds if there are enough electrons and enough polarisabiity

Carbon has four bonds in total. So for a carbon in a chain (which already has two other carbons attached) there are two hydrogens. For a carbon which has a single bond to one carbon and a double bond to another carbon, there is only one hydrogen. and so on. THIS PAGE, the wikipedia page that chemsiddiqui was referring to, has two more examples.

there's no need for a mnemonic. They're filled according to the n+l rule, sometimes known as the madelung rule. I've never seen it in a textbook but i always teach it to my students. It works.

a node is a region of space where the probability of finding an electron is zero. There are two types of node. Angular and radial. A radial node is spherical in shape, whereas angular nodes are planar or conical. the total number of nodes in an orbital is equal to n-1, where n is the principle quantum number. In the examples you gave, 2s has one radial node. You can't see it unless you do a diagram with a cut-away, since the orbital is basically a sphere inside a sphere. The 3s orbital has another layer on the outside of that. My avatar is an orbital which isn't usually occupied, I cant remember which, but you can see it has several (i counted 4) radial nodes, and two conical angular nodes.

nah this whole thread ought to be in general chemistry. i'll move it

your question seems to be asking how the orbitals are arranged spatially compared to each other. The answer is that they're all arranged on top of each other, which is why they're usually drawn separately, since the drawing would look a bit messy if you drew them all on top of each other. it's possible you meant how are they arranged in terms of their relative shapes, in which case klaynos's answer is correct. Dr P i'm afraid you're wrong, the 4s ones fill up first, then there's a point where the 4s gives up an electron in order to allow Cr to have a half full 3d, then it fills up again for Mn, then again the 4s gives up an electron to allow Cu to have a full 3d and fills up again for Zn. After the first row of transition everything goes normally until you reach the second row where things start to get confusing. After that exception start to become the rule and we give up trying to teach it.

each corner in the skeletal diagram is a carbon atom. the ends of lines are also carbon atoms. each carbon has enough hydrogens attached to make up its four bonds, although they aren't shown either, except when it's important to show them for some reason or other. Other atoms are shown as normal

UC, read the question. it says "assuming that the atoms are stacked on top of each other" that means we don't need to confuse people with crystal lattices and packing spheres

a lab i worked in for some time had once been checked for radiation only to discover one fume hood was fairly heavily contaminated with tritium, and had been for years, unbeknown to the dozens of people who had worked there.

the main factor in the release of CO2 from the diet coke IS actually the giant surface area of the mentos. It is also partly to do with the nature of that surface, but mostly it's just that for some reason the surface itself is microscopically very very rough, giving it a lot of pores, meaning the surface area is enormous.

thanks. dispersion tube. that's what i was looking for.

that's basically what happens with magnesium too. you don't get anything like a complete reaction. here's the video :0) enjoy

the glassware that consists of a glass tube connected to a frit, through which you can bubble gases in lots and lots of tiny bubbles. A bit like the bubbler you get for fishtanks?

in theory, yes, but the trouble with aluminum is is creates aluminum hydroxide on its surface which is almost impenetrable. Perhaps a drop of mercury might start it off, but i wouldnt want to try it like that. I tried it today with the turnings and it kind of works, but it's not as spectacular. One thing that i didn't foresee which i should have done is that the magnesium reacts with the test-tube itself, since that's essentially made of silica too. Don't expect to keep the test-tube afterwards :0) I also allowed the mixture to cool to very close to room temperature before tipping it into the acid, just to minimise the risk since the article didn't say whether they cooled it or not. I'll upload the video to youtube.

i want to try this reaction Ive done it once with magnesium turnings and it was OK but i didnt get a fireball, just pop pop pop. i think it was the silane that was popping and the magnesium that was fizzing.

I have some magnesium turnings but i want magnesium powder. do you think it's safe to grind it in a mortar and pestle? do you think it'd work?

PhD's don't come in subjects. each PhD is its own subject. if it was in the field of pharmaceutical chemistry you might get a job like that, although a word of warning: It's often harder to get a job once you've got a PhD, since it's better for the company to pay some monkey who just came out of university peanuts, rather than fork out for the real deal.

I took straight chemistry. It was a lot of fun but captain panic is right. Jobs for straight chemistry graduates are much less common than those for process chemists or chemical engineers Also good is biochemistry. The problem with biochemistry in my opinion is that it's taught by biologists, which means the chemistry is often skipped or wrong or jumbled.

ironizer, google is your friend. I could tell you what oxidation numbers are but there are twenty websites out there that can tell you better. And your instructor ought to be able to tell you too. sometimes face to face is easier than pure text. and of course don't forget your textbook.