Australia's Science Forum

Well thanks for all your help guys, I knew I could count on you =D> I have spent the entire day titrating and I survived! For someone who thoroughly HATES titrations it went surprisingly well and I feel quite calm and because of that I am very proud of myself :D this is what happened; Firstly the te...

Hi Kimm, so sorry been so busy with this stupid titration, blaaaa! I used 10% hydrogen peroxide, it needs to be freshly made up, I think once it didn't work because it was old... If you look at the results I gave you, you should be able to tell how much it froths up, should be no real action in the ...

Just got an email from her and she now asked for this 'it may be a good idea to give me a heap of HCl say 200 mL per girl (and another indicator) so the girls can practise titrating, before doing the aspirin titration. Make the HCl up to be a concentration so that 21.5 mL of 0.100 NaOH (in the buret...

Hi everyone, I am slightly confused today and i need your help please. I was just asked for standardized 0.100M NaOH solution for a titration prac, in the request she said this 'the 0.100 M NaOH needs to be standardised and you need to use a solution of HCl to do this'. Off course she has now left a...

I have always used fresh yeast for this experiment... Dried yeast does go out of date, I know that but if that could be it I am not sure, but I think the fresher the better

Sorry not so helpful,

Sass

Sorry I should clarify that a bit more... Because titration is an analytical technique, the proper method must be used if you are going to get meaningful quantitative results. In general you will always want to use the following procedures: 1. Make sure that everything is clean. Proper cleaning tech...

When I clean glassware for titration I do it as per normal protocol, but then I rinse it in distilled water. I dont know about using rinse aid for dishwashers, but it kinda seems to defeat the purpose a bit. What does everyone else think???

Sass

Oooops, crap! I read it wrong, I actualy use 1M NaSO4 not 0.1M... sorry about that

Hi Lizzieb, Sorry I didn't get back to you yesterday, but I was out on swimming carnival, yay! My head still hurts from the noise the girls were making :( I did what Lyn does, 0.1M NaSO4 and added some universal indicator until it was nice and green, dont need too much. Have fun and let me know how ...

Yes please!!! it is 9959 4460... Thanks Lada you are the bestest

lada wrote:We use PVA{polyvinyl alcohol) and borax to make bouncy balls. Never heard of sodium silicate solution for making bouncy balls. Do you have a recipe??
Lada

Do you have a recipe for bouncy balls, now that sounds like fun to me

Fibreweb! I am keeping my fingers and toes crossed, and as we do in sweden we hold our thumbs, that your leg is ok so that you can come back to work soon!

Sass

Hi Pommy,

Using the formula; M1 x V1 = M2 x V2 where M= is concentration and V= volume (mL)

10M x V1 = 0.05M x 200 > V1 = (0.05 x 200)/ 10M > V1 = 1mL

So you need 1mL of your 10M HCl in 200mL of H2O to make your 0.05M solution!

Good Luck,
Sassi

Hi Ellice,

just sent the fax through, let me know if you got it ok!

Sassi

Serrata has Ohaus balances too, they may be able to help you out! I hate Livingstone, everytime I have to call them, which has been everytime I have ordered something from them, this dumb ass woman answers, she is so unhelpful and you have to spend at least an hour trying to explain what you want, s...

If I remember corerctly I blended up about 10 each colour. You get nearly L with that many. blend it and then sieve it. If you have a look at page 6 there are a table that tells you how many mL of H2O and H2O2 to put in, it is in amongst my scribbles but it is the actual computer typed tables, if yo...

Would love too give them to you, but the change over is gonna be over the next couple of years, although pH sensor will be one of the first one to be replaced. When I find out I will let you know!

Did you get them all at the same time? Or is some older than others? If same age, get them to send you new ones (that work) ! If different age, tell me are they stored in a solution? If that is the case, most likely they have been dried out at some stage and thus damaged. Try calibrating if that doe...

Now that is interesting indeed :? Is there a massive difference or does it come down to decimals? If that is the case it could just be a matter of different probes different degrees of accuracy. However if there is a massive difference, then I can only see one resonable explanation, they are not cal...

Nice one, I really like that! Soo cool