Recent content by martin

  1. M

    AQA exam Board Water purification required prac - concentrations?

    Sea water is around 3% sodium chloride, plus other soluble salts.
  2. M


    You do know that for it to work you have to get it very high temperature's, if they insist then get the thinnest bones possible.
  3. M

    Help needed - reacting potassium iodide with sodium nitrate.

    We do the Potassium/ sodium Iodide Lead Nitrate precipitation reaction as a demo for the no change of mass teaching. that cuts down on the amount of waste that needs to be stored for disposal by waste company later.
  4. M

    Copper (II) chloride crystals?

    Concentrated copper salts are hazardous in there own wright, harmful if swallowed, irritating to skin, not good for eyes. Try copper acetate if you have any. It is not very soluble in water so dissolve in warm/hot water and will get a saturated solution or near to, for the crystals to grow from.
  5. M

    thermite disposal

    we do the termite reaction on a small scale say 12-15g mixture and react it on a sand tray, ignition started by magnesium. I throw the end products in the bin. As all you will have is Iron, Aluminum oxide and Magnesium oxide and some sand.
  6. M

    Prep room refurbishment!!

    Thank you for the sympathy, you know what is most annoying, is I measured up and listed every cupboard shelf and draw in my old preproom, I counted every gratnel tray and where they were to be found , ie in the racks or in cupboards. I measured the area of work surfaces, even the area of floor...
  7. M

    Sodium thiosulphate

    Very true Emil the Ammonium Iron (II) sulphate is more stable, even the solid it`s self lasts longer than the neat Iron(II)sulphate.
  8. M

    Prep room refurbishment!!

    Sorry to say it is to late they have completed the fitting out, and no listend to me or read the detailed list of cupboards shelves and bench surface I had in the old prep room. I even measured up window sills and the are of the floor used for storage. But they are moving 3 science prep rooms...
  9. M

    Prep room refurbishment!!

    Long these lines advice needed. We are moving into a new build and the cupboards are not deep enough to hold our burette or pipette trays. I attach a photo of a burette tray we have. I have 4 of those and 9 trays about half that size for pipettes and none will fit the cupboards in the new build...
  10. M

    Sodium thiosulphate

    Thiosulphate does decompose over time, but I have kept 0.1M for 12 months or so in a black plastic bottle and had no problems in using it. With Iron salts then the acidifying the solution keeps them stable for a while but they do not last for much more than a term I would say.
  11. M

    Fume cupboards

    When I get our fume cupboards services through Chts they always send an on line form to fill ask what chemicals have been used in the fume cup boards.
  12. M


    I have been looking around, and found that Breckland offering 25g of 2,4-DNP. check them out.
  13. M


    I believe that is correct, which was my surprise at the 100g sale as i have previously only bought 25g lots, which I have done 3 times in my 10 years here.
  14. M


    I forgot to say that the delivery charges are blood expensive and will probably be close to doubling the price,
  15. M


    Sigma Aldrich sell the solid, unfortunately only 100g lots for £48.50 excluding vat. Though that amount will last years, and so long as kept damp is safe. I am old fashioned and have never had any problems with storage of the solid, the big problems now is the paper work required to be submitted...