fermions

Is superfluid a kind of macroscopic quantum phenomenum ? there are many pictures of superfluids climbing up the surface of a bottle...

I have a question here... if Cu wants to have a full shell why can it sometimes form Cu2+ when Cu+ is much more stable? thanks

I've got some questions on neutrinos I've read that neutrinos are always left handed (or right handed forgot...) and the explanation is that neutrinos always travel in light speed so nothing can pass it and see it right handed sorry if my statement is confusing but have anyone read about it? thanks

talking about the neutron star... I heard that the electrons are actually squeezed out by the gravitational force and leaving the nucleus behind so it's something like neucleon star... dunno if it's true or not...

thanks... I understand a little bit now... does it mean that k varies with the number of atoms in the lattice? and is the probability of finding an electron near an atom is greater than that of between the atoms? If so, is it because the atoms (or should I say the positive ions) attract the electrons so it changed the wave function of it?

hello, I would like to know briefly how the Bloch wave is simliar to a wave function of an electron and what's the difference between them also how did the Bloch wave affect the energy of the electronic band I hope you can understand what I ask as I was just reading some elementary books about it thanks

I've experienced it before... our chem department head always like to put questions that we're not supposed to know in the exam... and he ended up getting the answers wrong also...

I would like to ask about the difference between water vapour and steam.... is water vapour what steam has condensed? and can we see steam if it is a gas?

thanks a lot now I understand...

so under normal pressure steam is always 100 degrees right? so like steam above water surface it's always 100C as it's an open system am I correct?

If we boil a beaker of water, then we put a thermometer above the surface... that is, we are checking the temperature of steam and we always get 100 degrees Celsius under normal pressure right? so is it possible to have steam over 100 degrees? how about we collect the steam and then heat it up is it still 100 degrees? thanks

I see... maybe it's so called out of syllabus at my level (even the public exam states the answer as cannot be decomposed) maybe I'll learn it at A level Even the Haber process and Le Chaterlier's Principle are not required in my exams, I bet I'll learn more at A level thanks anyway

my teacher used to tell me sodium carbonate doesn't decompose on heat.... can the decomposition be achieved by a Bunsen flame? (if not I think that's why the teacher doesn't tell me the truth) thanks

I think that some carbonates don't decompose on heat e.g. sodium carbonate

theoratically I think it's 1:1 but at the same time insolubel CaSO4 will be formed that may left some Ca(OH)2 unreacted...

I think that KE and momentum is considered as one whole thing when considering four dimensions... but I'm not sure about it...

I think that's what s/he means... anyway I want to add a question related to that.. copper hydroxide is insoluble in excess NaOH (or alkaline) but when ammonia solution is added to it... it forms tetramminecopper(II) complex ion and dissolves... so why doesn't it become Cu(OH)4 and dissolved in excess Naoh also... and my teacher says the reaction between NH4+and OH- are not reversible because strong base displace weak base and it can't go the other way round... I don't quite believe in my teacher... so when is this displacement rule applicable? thanks

I heard that light can be affected by magnetic fields... but I still don't quite understnad I think one of the effects has some problems with polarization

em... could anyone state what kinds of contradiction might arise if information can be transmitted faster than c... and the so called instantaneous transfer of information during entanglement doesn't seem to cause any confusion... so why can't information be transmitted faster than c after all... just because the special relativity states the c is the fastest speed than we cannot exceed it? thanks

hello I've been thinking what contradiction will arise if information can be transferred faster than the speed of light... for example.. suppose the same old example... the sun suddenly disappeared but we somehow get information before the incident reached our eyes... we know it will happen but we cannot alter it one contradiction is that there will not be any more relative motion... but what other more significiant problem will arise? anyway is it possible to have an object that is absolutely at rest? thanks

http://arxiv.org/abs/astro-ph/0305457 <- one of the few links about VSL anyway isn't there always news saying that light maybe travelling faster in the earlier times of the universe and it's been slowing down?

anyway I've heard about the varying speed of light theory... it seemed to suggest that we don't need an inflation theory to explain why the universe is like what it's like at present... and also that energy is not conserved has anyone heard about it?

oh.. I think I'm taking the HKCEE this year.. anyway GSCE is not quite the same as the HKCEE.... the GSCE is easier but seems to have a wider syllabus... and does not go into the topics as deep as HKCEE... hard luck I'm not born in UK

oh.. I think I'm taking the HKCEE this year.. anyway GSCE is not quite the same as the HKCEE.... the GSCE is easier but seems to have a wider syllabus... and does not go into the topics as deep as HKCEE... hard luck I'm not born in UK

I think one can use the molecular orbital theory to deduce about it.. but I'm not sure about it.. the energy levels of the orbitals are so confusing...