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Okay. Another urgent query: Does universal indicator contain high pH initially? So if you had a reaction and wastesting for pH increase, it would be hard to see?

1. Are potassium complexes dangerous? I have no clue... heh ;) 2. That's why it doesnt make sense. If it's aqueous solution, we get a high voltage running, wouldnt Cl-(aq) react with water forming H2 and Cl2 or something? Or K+(aq) might also be reacting to make K(s) at the same time... I'm not...

Why doesn't electrolysis always undergo the reactions predicted? I know about electrolyste concentration, gas pressures, what electrodes are, current, voltage, but I don't know how they impact, except for concentration, I think. With the voltage one, should the voltage be much, much higher than...

Ah, water ;)

1. An experimental source of power for a heart pacemaker involves implanting a zinc electrode and a platinum electrode into tissues in the body. Oxygen present in body fluids is reduced at the platinum electrode. Before this method of power generation if used, what further investigations would...

3) Oh, whoops, i was looking at 5. I got the numbers mixed up, sorri. Unsure whether i asked this before but I had itcircled, so I need help... *sniffs* 1. Early attempts to produce aluminium by electrolysis of aqueous solutions of aluminium compounds were unsuccesful. Use the table of...

2) So are you nodding at the fact that the battery goes dead or nothing would would happen? b. it would blow up? heh... 3) What do you mean? it does, but the write the equations bit doesn't. I have trouble with that :'(

Hahah, whoops, didnt see the date... But that's really weird. There was a link to this from another forum (i dont go wandering through past threads, at least, I dont think so *frown*), so it was 'used' recently or something. Maybe a moderator just moved it.

I'm just a little confused about this topic. I understand the thinking process when working out these problems, or by drawing tree diagrams and such, just dont know how to use the formula P(A given B)= P(A intersecting with B)/ P(B). Working out P(A intersecting with B) is a problem because...

This question is confusing, because drawing all over the table of standard potentials didnt work. A student carries out experiments with four reductants, H2, P, Q and R. metal Q reacts with a solution of PSO4 to produce metallic P. gaseous hydrogen will reduce cation R2+ and and one other...

That's exactly how i remember it ;)

1) Yes, that's why it's ambiguous, and... I'm confused! 2)... electrons would keep going from A-->B, until the battery's totally dead? Or maybe nothing would happen? 3) b) Not sure why build up of gas is dangerous =S 3. Really? These calculations arent in the syllabus? Maybe i should've...

lechatelier's makes sense, but I thought it was something along the lines of the changing order of the reactions listed in the table when you change concentrations around? Dont know EXACTLY how it works, though... Does loosing voltage mean the reaction has less tendency to occur, or has less...

Several pressing questions :) I was told by one person that it wouldn't matter if the cells aren't under standard conditions (when doing experiment). I've read that the the order in the electrode potentials table can change if you don't! =S Eg. for a particular cell which half cell you connect...

1. A student working in the laboratory spilled an iodine solution over the bench, causing a dark brown stain to form. Suggest how the student could remove the iodine stain. Suggest how the student could remove the iodine stain. I am aware you would probably go and pour something over it to...

6) (I shan't ask how... ;)) 1) just this bit ... huh? 2) Well I don't know... maybe if people realise coal's not going to be eternally there, they'll figure out other energy sources to use, but if they can't, or they have to avoid it for reasons like convenience or cost or things, the rate...

1b. ah, ok. All calorimeters are prone to energy loss yes? 2. Interesting the way you've described it xD 3. I have no idea either... (although not sure I understand... )

A 0.254g sample of black coal was burnt in a bomb calorimeter. The calorimeter contained 300ml of water which rose from 19.25C to 24.92C a) Using the specific hat capacity of water, calculate the heat of combustion of the coal ... which i've done b) Is your answer likely to be higher or lower...

3) 'oxygen pre-diffused into the coal'? 4) heheh ;) 5) Thanx, wrxsti :) you seem to know quite a bit about that 6) One confusing thing: How does water contribute to the greenhouse effect? Thanks to both of you ^^ PS. Yes she does get a bit carried away (she's one of those passionate chem...

Some random questions I was wondering whether someone could help me out with: 1. A hand-warmer purchased by campers and skiers consists of a sealed outer plastic bag and an inner perforated plastic bag containing powdered iron, water, salt and sawdust. When the inner bag is taken out and shaken...