Recent content by siewwen168

The vapour pressure of a pure liquid solvent B is 75 kPa. When an unknown mass of non volatile solute W was added to 0.2 moles of solvent B,its vapour pressure drops by 20 kPa. If the relative molecular mass of W is 118,how much of W was added to B? A 5.07g B 8.58g C 23.44g D 64.9g i...

thanks for your explanation..but which one is the most suitable answer?or no answer at all?

because i thought D is the wrong answer,ideal gas don't have intermolecular forces between molecules :confused:

hello,i have question to ask here. :smile: 1. which of the following is not correct for an ideal gas? A. the average kinetic energy of the gas increases with temperature B. the force of repulsion between molecules is proportional to the distance between them C. the gas...

Can anyone here explain to me the role of auxin in cell's elongation? :confused: I think it's related to the acid growth hypothesis,but i need the explanation on how this hypothesis works. :rolleyes: thanks a lot for anyone who help :smile: o:)

question again. thanks bout the answer for changes in standard. :smile: for second question ,0.00341g of iron have 0.00341/26 moles of iron atoms ,right?the answer will then divided by 4 because 1 molecule of haemoglobin contain 4 atoms of iron.1g of haemoglobin will contain the moles that...

hi,actually from my calculation of the first question,the mass of N2O4 that i got is 805kg,but the answer given is 875kg.i don;t think that i have anything wrong in my calculations,so i need your answer.Because those question got a lot of mistakes,haha,maybe I'm just lying to myself.but pls,can...

Hello,there are some question about physical chemistry to be asked. :-p 1) The space vehicle,Gemini,started its journey in space with 322kg of liquid fuel, CH3NHNH2. This fuel is oxidised by dinitrogen tetroxide,N2O4,to form nitrogen,carbon dioxide and water.hat is the mass of...

does anyone know any websites provide online chemistry textbook,a level one? :-p or websites that provide revision site for all topics for alevel chemistry? :wink:

Does anyone know which website contain online biology textbook,A level one? :cool: Or which website provide revision site for all topic for A level biology? :smile: thanks a lot for anyone who help :-p

thank you thank you for your explanation.I hope u don't mind if u can tell me the total pressure that CO2 and O2 exerted before H2 is added in. :wink: i found out that the website that u recommend me is very useful,especially the MSN one,that is for general chemistry ,right? can i know the...

sorry sorry,i still don't get what u mean. the first question,i had already count,but i just can't get the answer,that's why i need someone to show the calculations for me.thanks for the second one,i need some explanation,i don't want to just accept the answer,but i want to know why.if i just...

some question need to be solved! 1.) A container contains 60cm3 of CO2 and 40cm3 of O2 at room temperature and pressure conditions. If 200cm3 of H2 at room temperature and pressure is now injected into the container, which of the following would happen? :confused: (a) The partial...

hi pack rat2,thanks for your help,i think your information is very useful to me.thanks alot.

hello :-p i want to ask about the deviation of real gases under low temperature and high pressure. :-p my reference book states that carbon dioxide deviates more than nitrogen and hydrogen,this is because the order of boiling points of is decreasing from carbon dioxide to hydrogen.this...