Australia's Science Forum

Which prac is this? Do share, I would like to know. Do not know the answer though. How about we road test new servic;e Science Assist Sounds like Pearson Science 10, 4.2.1: Investigating a Metalic Element. Mix 0.3g silver nitrate in 40mL distilled water, heat on hotplate, add in 0.5g agar-agar, set...

Thank you for that. The PE teacher was wondering if storing 20-30 of them together may effect them. We know to store them away from magnets etc. but can they have a negative effect on each other? J Not noticably. Compass needles are fairly low strength magnets. The problem is with strong fields per...

Does anyone know what to stain DNA with and where to get it. After extraction, it would be great to look at it! Any of the usual cell dyes will work. Toluidine Blue , Methylene Blue , or Aceto-Orcein will all stain the nucleus. Methylene Blue seems to work quite well, and is commonly suggested in t...

I have been asked to look for a prac that will test the energy in sugar. I have tried various ways of typing in the question in google and here and have not found what the teacher is looking for. It is all in knowing the right terms. Measuring the energy change in a reaction is called calorimetry ,...

Main tip: Do not use acid!
FeS + 2 HCl = FeCl2 + H2S (g)

Try a potassium permanganate wash.
3 FeS + 8 KMnO4 + 4 H2O = 3 FeSO4 + 8 MnO2 + 8 KOH

I have tried making calcium hydroxide solution from "The Laboratory" book however it hasn't been going milky in experiments. Does anyone have any ideas as I need "workable" solutions for a yr 10 prac test. The solid should not decompose as long as it is kept reasonably dry. Dry ...

Yes. To acidify a solution just means to lower the pH below 7.0 using a slight addition of an appropriate concentrated strong acid. That is all. The only 'trick' to it is to choose an acid that doesn't form a precipitate with your solution. Usually this simply means to match the acid with the anion....

What is the recipe for making up maltose (1%) or do I just dissolve in water? Yes. Although 1% maltose is almost saturated 20°C, so a little heat may be needed to encorage disolution. For every 100mL you want, disolve 1g maltose in about 80-90mL of hot water (50°C), allow to cool and then dil...

If you have access to RiskAssess,they have done an assessment on the Van Der Graaff. The system provides the following information for staff to assess the risk. Van de Graaff generator Potential hazards Electric shock is generally harmless since current is so small; might cause injury to impaired i...

I've never really used it. It's a pH indicator with a similar range to phenolphthalein but turning a deep blue colour instead of bright fuschia (both are clear in acidic solution). I believe it has a sharper end point and more visible colour transition. If accuracy really matters, go for thymolphtha...

Hi everyone i'm having a brain fade. Can someone help me to make up a 3% Zinc Chloride solution cheers :oops: Rell We all have that happen. :console: It's just 3% by weight per volume . Which means: 3g/100mL. That is all. Not even a molecular weight in sight. Just adjust the mass proportionate to t...

Oh dear. Students and staff evacuated as science building catches fire at Mitchelton State High School ( Read more ) STUDENTS and staff have been evacuated from a burning Brisbane school. Fire broke out in the science block of Mitchelton State High School about 8.30am. The blaze was contained by 10a...

mtg wrote:where does the Potassium go?

Nowhere. The potassium ions remain in solution.

We don't use any in our school. As far as I know it is a banned chemical..... It is banned by the DETE specifically for use in the preparation of hydrogen with manganese dioxide, but in practice seems to be treated across the board as being under a blanket ban. That is probably safest, since if it ...

To be clear: Tertiary alcohols can be oxidised by potassium permanganate (esp. in acidic conditions). It's a strong oxidizing agent, so that's not too unexpected.

The puzzler is that the secondary alcohol didn't oxidise at all when it should be more prone.

:mail: You just need to add 1 mole KSCN to 1 mole Fe(NO3)3 in an acidic solution (use nitric) and dilute to volume. Then store away from light. The acid keeps the Fe{3+} ions stable and prevents the formation of Fe(OH){2+}. The thiocyanateiron complex will form in an equilibrium reaction; a blood re...

No. That does not sound right at all.

Tertiary alcohols are supposed to be highly resistant to direct oxidation. Certainly secondary alcohols should be more easily oxidised.

What exactly are the names of the alcohols that you have?

I also have an extra long stretched out slinky. A teacher thought it would be cool to put weights on to it and hang it over the balcony and keep adding wieghts until it wouldn't rebound any more.... There is only one thing I can think of to do with it - and I think i would end up in prison! :consol...

Ian wrote:Curie,
Is that the KI or the MnO2 ?

Ian

MnO2.

rae wrote:Graham did you use saturated KI or solid KI?

I used saturated as it was handy for the test, but solid will work just as well.