Australia's Science Forum

I obtain bigger crystals by keeping the container in a warm place and reducing the rate of evaporation to a minimum. I use a disposable plastic food container with a cm depth of saturated solution and leave the lid covering in place except for a narrow gap at one end.
Cheers,
Fran

When I first came here it took me three weeks of scrubbing just to get the lab glassware clean and free of rust stains. I banned ordinary steel wool for cleaning electrodes and switched to stainless steel wool. I soak the stainless overnight to loosen the soap impregnated in it then rinse clean. It'...

Also check the posts in 'Peptone vs Pepsin' in recipes and pracs.

Cheers
Fran

I keep a can of 'Silvo' silver polish handy in case of an accidental spill in the labs and it works fine on benches and floors. Reading the can it's flammable and contains 6g/L ammonia but doesn't give a full list of ingredients. It's never done my hands any harm when cleaning silver electrodes at w...

So what about the bottles of HCl that one buys from pool shops? Surely the class remains the same even it is intended for a different use. (Serious question - not a smarty pants one) I'm with you Smiley - if it's HCl it's a class 8; if it's a class 5 it must be a different chemical. Would anyone ou...

Can't the pool company deliver or organise a courier to do so. I'm sure they must arrange for delivery to other clients. Worth asking anyway.

Hi Annette,
Check out Southern Biological's "Glitter Bug", I think it's what you're looking for.
Cheers,
Fran

Hi Annette,
Try 0.1M acidified ferrous sulfate too - make up 0.1 mole ferrous sulfate solution and add sufficient 1M sulfuric to give a pale green colour).
Cheers,
Fran

Hi Sassi,

The attachment is a prac we did at a school I used to work at and it worked well.

Cheers,
Fran

Hi natfrog,

According to Vogel - Elementary Practical Organic Chemistry, Lucas' Reagent is prepared by dissolving 1 mole of anhydrous zinc chloride in 1 mole of conc HCl. Keep cool to avoid loss of hydrogen chloride.

Cheers,
Fran

Hi Mother,
Omega Scientific in S.A. also have a fairly good selection. Phone (08) 8289 4311; Fax (08) 8289 4322; or check out their website http://www.omegascientific.com.au. Click on price list, then earth sciences to see what's available.
Cheers,
Fran

Hi Sassi,
May I also have a copy of the prac please.
My fax number is (08) 9444 8538 (Attention Fran)
Many thanks,
Fran

Hi all, Thanks very much for your assistance and ideas. Being a senior college (17+) we don't have a D & T centre and can't ask parents either. As a tradesman, my husband is very handy in a workshop and sometimes does jobs for me at the weekend, but I liked the sound of the Haines one and asked ...

Hi everyone, I've checked catalogues and been online and cannot find what I am looking for, so now I'm doing what I should have done to begin with - post on the Chemtalk forum because with the amazing diversity of knowledge someone is bound to know. Where can I buy a bridge building kit made of wood...

Another site that may be worth a look is Cooloola Rocks and Minerals in QLD. Perhaps a bit on the expensive side for most school budgets but some lovely specimens available if you're a collector.
Cheers,
Fran

Hi Mother,
Some years ago we had problems with thermometers 'losing' their markings. The remedy was to make a paste of barium sulfate with indian ink and rub it into the markings. Any excess can be buffed off when dry leaving now visible markings.
Cheers,
Fran

Thanks for the information below Ocker: "Acidifing turns it green, but can affect reactions." Using acidified FeSO4 we get all the right results with the solutions we use for precipitation reactions here, but I'd like to know what reactions can be affected because - surprise, surprise - te...

Hi Ocker, I will try your suggestion and add a nail to one of my bottles. When I make up Fe2+ the brown Fe3+ colouration appears within minutes (probably cheap chemical!). I add just enough 1M H2SO4 to reduce it back and it remains in the 2+ state. Because it doesn't need a lot of acid there isn't a...

When I buy a new bottle of peptone I weigh 5g lots of the powder, store it in small (40x60mm) snaplock bags, store the bags in a sealed plastic container and keep the container in the freezer. It doesn't stop the peptone from darkening or going hard, but it's alot easier to peel the plastic bag off ...

Hi Maree, The St. John's have a 100g tube of Laerdal artificial blood concentrate available at around $28 (item no in WA is 5339). Can be greatly diluted as, like blood, a little goes a long way. As far as I'm aware it's non-toxic and it saves mucking around with stains to get authentic-looking bloo...