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a) HBr + NH3 -----> NH4Br HBr is an acid, NH3 is a base. As HBr combines with ammonia, it gives up a hydrogen atom, defining it by the Bronsted-Lowry definitions as a proton donor. The base, ammonia, receives this hydrogen atom (as well as the bromide), defining it by the Bronsted-Lowry...

Thomson built a cathode ray tube with charged parallel plates to provide a uniform electric field and a source for uniform magnetic field. Thomsons experiment involved two stages: - Varying the magnetic field and electric fields until their opposing forces cancelled, leaving the cathode rays...

A photocell is a device that uses the photoelectric effect. These devices include photovoltaic, or solar cells, which convert electromagnetic energy, such as sunlight, into electrical energy. Other examples are photoconductive cells and phototubes. Modern solar cells use silicon and gallium...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Add NaOH, white precipitate forms. She may have used sulfate to precipitate two ions, barium and chloride, then used Ag+ to separate chloride from the salt. If there is still a precipitate, then barium is a possibility of being...

HAHAHAH, cant get much funnier, answered by a person who posted another question that has been answered. Analyse how knowledge of the composition and properties of acids has led to changes in the definition of acids. Early definitions of acids were based on their properties, including their...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Someone already did a question very similar to that, and i gave an answer to it as well. The Reactants are volatile and yet need to be heated to reach their activation energy. Refluxing cools the reactant gases and condenses them...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Is this a first hand investigation? Ill try at least haha. Local Catchment Area: Warrell Creek Many tests were done with the sample of water obtained from this river as tests for anions / cations. The only anion found was...

This is a very gay question indeed, there isn't even marking notes on it. The Reliablility part may be addressed by the mention of hydrogen atoms in each human body, ect. But yeah, I wouldn't bother with this haha.

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Geiger-Muller Counter. This device also uses ionising properties of radiation. It is particularly good for measuring beta particles, thought it can be made to work for alpha and gamma rays too. The beta ray enters through the thin...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] The Reactants are volatile and yet need to be heated to reach their activation energy. Refluxing cools the reactant gases and condenses them returning them to the reaction mixture for continued heating. The gases would otherwise...

I argree with this. I've seen people ask this way too much and its starting to give me the shits. Just use the physics formulas, so at least if you do get it wrong, you'll get marks for the working out, ect, like the others mentioned.

Woot! I've been trying to figure out the name of this piece of crap for agessss now, at least 3 weeks haha. Thanks man, the other safety precautions were ones i werent aware of too.

Cast iron would have been an absolute pain in the arse to make boats out of back in the 1800's, and its kind of like pig iron, so it corrodes rapidly. If it was used, it would be in the period of introducing iron to make boats out of.

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] Nice lets pretty much repeat questions, just with different wording.... Haber developed a method of porducing ammonia by reacting together hydrogen gas and nitrogen gas at 400 degrees C and 250 kPa with an Fe3O4 catalyst. This was...

I would say, mention the two people firstly. Then talk about how reach one of them has its advantages, and that AC is the better one due to less line loss ect, then how Edison tried to say AC was bad, and electricuted animals and said they were "westinghoused". Then mention that nikola tesla...

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] A buffer is a solution that is able to maintain a constant pH; even the addition of a strong acid or base does not change its pH. The buffer solution contains approximately equal amounts of a weak acid and its conjugate base. The...

I can't answer your question on the scaling as I have no idea, as it changes each year, but the syllabus dot points are excellent, if anything, the best way for knowing all the content. Its a fair bit to cram though, if your only starting now with 4 days to go haha.

I think this should've been posted in the shipwrecks section, it looks like a question only for that option

Re: [-- Official 2008 HSC Chemistry Pre-exam Study Thread --] The Haber process is the process of producing ammonia from gaseous hydrogen and nitrogen. 3H2(g) + N2(g) ----> 2NH3(g) Because the system can come to equilibrium and is exothermic, conditions need to be monitored...

Microscopic membrane filters can be used to remove fine particles and micro-organisms from water that cannot be removed by the normal treatment. Membrane filters are made of thin polymer sheets with fixed pore sizes. The commonly used polymers are PVC, polycarbonate, polypropylene, polyester and...