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Do you wanna know how its manufactured etc? I've got some notes on production of it.. just yell out if u want them. Biopol has been used in the manufacture of dissolvable medical sutures, since the polymer is biodegradable. This minimises patient discomfort, since stitch removal is not...

Why is it 1.6g?

How about any CH3COO- ions that undergo hydrolysis to produce OH-? That's why in weak acid strong base titrations the equivalence point is somewhere around 8-9.

TBH HSC did affect my social life. Especially nearing trials and the exams themselves... people would be asking me to come out with them etc.. it has been hard replying with "Nah, i gotta study" for the past 2-3 months. I reckon the HSC made me find out who my true friends are. So many...

But that's different from saying that they BOTH have a pH of 3. You can't actually determine the [H3O+] of a weak acid, because you don't know to what extent it has ionised. Whereas, with a strong acid, you can, because virtually all acid molecules ionise. If the solutions both have a pH of...

http://community.boredofstudies.org/showthread.php?t=34578 Have a look in the first post in this thread (you have to scroll a bit down to find 2001 MX1) Actually.. the E4 cut off is 45-52/84.

just remember that adjacent polar functional groups (eg. hydroxy) react to form a small molecule such as water. ie. per one bond formed, one small molecule is released (or per two monomers reacting/joining, one small molecule is released).

doesn't the neutralisation depend on the [H3O+] ? For any acid, weak or strong, if they are both pH 3 , then they must have equal [H3O+] , yes their acid concentrations will be unequal... but doesn't neutralisation depend on the [H3O+] ?? Confucious lol

Commercial radioisotopes are produced in nuclear reactors as well as particle accelerators. Example: Technetium-99m is a commercial radioisotope widely used in medicine for diagnostic imaging purposes. Molybdenum-98 is bombarded with a neutron in a nuclear reactor, to produce Molybdenum-99...

Seeming as very few did the globalisation response.. it could work for OR against those who did the globalisation essay. Since you'll obviously have some kick ass essays in there.. the mid-range might not get as good. Less room for competition.

q = 0.200 * (4.18*103) * 24 q=20.064kJ DeltaHc = q/n 1367 = 20.064/n n= 20.064/1367 n(ethanol) = 0.0147mol m(ethanol) = 0.0147*46.1 therefore, m(ethanol) required = 0.68g (2 sig. fig.) Next calculation: 2.5L of HBr(g) and 1.6L of NH3 (g) measured at 25C and 100kPa are mixed. They...

well in order for there to be pH3, each acid solution must have the same [H3O+] . So I would agree with above poster in saying Equal volume. but then the confucious thing is, CH3COO- ions then undergo hydrolysis to form OH- ions in solution. (maybe this could mean u would need less to...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Lavoisier initially suggested that oxygen was the acidifying principle in acids. However, later research discovered that not all acids contained oxygen. Davy then suggested that hydrogen was the acidifying principle in acids...

Well, in 2001, the E4 cut-off was 48-52/84. And I reckon this year's paper was more difficult than 2001. I'm just going for an E3 anyway.. Anyone have an idea wat E3 (40-45/50) cut-off will be around?

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] High-Density Polyethylene consists of long, unbranched and aligned molecules, thus making it a strong, sturdy and versatile material. Hence, since it is a dense plastic, HDPE is used in the manufacture of bottles (such as for...

Well, to be honest, I'd rather have an extra week of NOT partying... and calmly study my ass off for my last HSC exam, give it all I've got and then get an awesome result in the end. We only have one chance with the HSC anyway...

lol they might accept both answers

well your moderated assessment is determined by the top exam mark if you're ranked first. but then again, the first ranked person will most likely attain the top exam mark in their cohort anyway.

not unless ur ranked first

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Eutrophication involves the addition of nutrients, such as phosphates and nitrates, to waterways. This leads to the thriving/growth of algal blooms. Subsequently, these algal blooms at the water surface block the penetration of...