Hey, quick question which hopefully someone can help with, I need to work out mole fractions from a proton NMR spectra, we've been given the integrated areas under the peaks, so I assume it's using that, but we haven't actually been taught how. Thanks
hiii all the chemists out there, ahh i really need hepl, has anyone come across partition coefficient? anyone know anything about partition coefficient!? rly need help!
Quick thermo question: When dT=0, dU=0. Why is this and is there a mathematical way of proving it? Our lectures give reasons for constant volume and pressure relationships, but not constant temperature . Many thanks!
(...) explain why calcium hydroxide is more soluble in water than magnesium hydroxide?
Both calcium hydroxide and magnesium hydroxide are solid elements. In terms of the solubility in water, a solid element is more soluble when it has an higher temperature. Calcium hydroxide is soluble by 20 °C (I don't know at the moment what it is in Fahrenheit.) and Magnesium hydroxide is soluble by 18 °C. In related to that calcium hydroxide has a higher mass unit per volume than magnesium hydroxide - 1,7g*l^-1 compared to 9mg*l^-1. That is to say 1,7g per liter solution is soluble in water for example. Solubility increase at high mass unit per volume and decrease at low one. Do you get it?
What did you mean with your first question. I'm sorry, but I'm not an Englishman! I didn't understand you.
I have no idea. I think there are not so much chemist in this forum at the moment. Are you interesting in chemistry? which doctrine is your favourite? Have you any paragons in chemistry and why?
What a pitty... Is there really not a member who is VERY interesting in chemistry (not only for exams)? Is there not a member who want to talk about one? I'm bored...
That sounds interesting. I'm interesting in structure of atomic time and time again. I can't believe that a particle is soooo unimaginably small and consists of smaller particle charge. Do you know for instance a compound between a neutron and proton need an energy over 250,000 J to disrupt them? that is a fair bit of energy. A mountaineer for instance need so much to climb a mountain. Is it not fascinating?