Australia's Science Forum

Hi All

We used the potassium permanganate crystals with straws/forceps for observing convection currents. In recent times the new containers of potassium permanganate (Chem Supply) contain very fine crystals and it is impossible to pick them up like we used too.
Does anyone know where I could find coarser crystals? Do you use an alternative to the Potassium Permanganate? Would the Condy's crystals from chemist shop be coarser (I have never bought these)?

Thanks
Rita

Pretty sure the teachers at my old school used tea leaves for this prac. No issues then with risks and no problems with disposal.

We use tea leaves here too.

Try a Chemist

I had the same problem. So I made up a small amount of saturated solution and then poured it into old petri dishes and allowed crystals to form. Takes a day or two to dry and crystals to form but it works. Just store them in a speciman jar and use them only for convection prac.
Cheers trish

Cunning idea trish

Our Potassium Permanganate jar has had the eyes picked out of it and is dust too so looking forward to trying this . ......sure it would be easier to buy a new jar or use tea leafs , but wheres the fun in that .

Just remember that potassium permanganate should not be tipped down the sink. it needs to be collected as waste. I read that on the Scienceassist website. Probably takes away a bit of the fun!

LOL , maybe for you Merilyn , but us in the DET are still waiting for the new CSIS and accordingly we can still dispose of it down the sink .....and do other apparently naughty things until further notice.

anyone know why Scienceassist suggests not disposing down sink? that would save the sinks when the darlings chuck it into the sink and don't wash it down!!

Sharon

Hi Sharon
Checked on the SDS and it is "hazardous to the aquatic environment - acute hazard". Riskassess also say it is "very toxic" to aquatic life.
That is good enough for me to not tip it down the sink.

Just as a side issue - don't they use potassium permanganate at the beach to show where rips are?

Very good point annnos,

Maybe they used to once upon a time, but what I've read just refers to environmentally safe dyes.
Perhaps you could do some searching and find out for sure.

It's "very toxic to aquatic organisms". R50. Going on the MSDS toxic if swallowed too. All in all he's a bad dude. And dont get me stared on the stained glass ware!!!

When my brother had chicken pox, my mother bathed him in potassium permanganate (as prescribed by doctor). She was heavy handed and he came out yellow !! :O

AnnNos wrote:Just as a side issue - don't they use potassium permanganate at the beach to show where rips are?

No they use flourescein

You can mix vitamin C (Ascobic ACid) you keep adding till it is murky brown - it is now Manganese Dioxide which is ok for waste disposal ...

Hi,
Funny, I used Potassium permanganate before to heal gold fish in the fish tank when they looked sick, and it worked. I don't have them anymore, they died of old age.
?? Ines

They used to use it to help heal horses' hooves (as in All Creatures Great and Small). It had its uses but antibiotics have taken over! mmm, not sure if that is such a good thing.