Australia's Science Forum

Always remember that pressure cookers are sold in shops where idiots can buy them . They have to be made idiot proof and safe or we would be hearing reports on the news of people being killed or badly burned by them . Depending on the size if them , you’ll be lucky to fit more than about 25 plates ...

Side note: The plates shouldn't be completely sealed by sticky tape. There should be a gap. If you're using parafilm, it goes all the way around. It's to do with tape creating an anaerobic environment and growing the wrong type of nasties. So are you saying being sealed with parafilm is ok because ...

Thanks Marama T. I didn't know that! I do hate to do it though. I do it in the fume hood but the smell still escapes. I have only actually done it twice here since I started a year and a half ago. It would be good to find an alternative. I will defo investigate getting a pressure cooker.

Thanks for the info bigmack. So you think the bleach would get in if submerged overnight even if not opened? I'll probably give that a go. And will also investigate the pressure cooker idea. They scare me a bit. I have never used one.

OK. Thanks. I was opening them up and soaking them in bleach inside a fume hood, so hopefully nothing spread. Much more preferable to wrap and throw away if that's acceptable.

Would I be able to wrap sealed (with parafilm) used agar plates up in a bin bag and place in with general waste? Or should I be doing something else with them? Previously I have opened them up and treated with bleach, but I have ~200 to get rid of and that is not an appealing job. (We don't have an ...

Until recently we were using 0.1M (oops!) , which had been set up in droppers before I started. Until I realised that 7-10s could only use <0.003M. So I set them up as 0.002M. Still works just as well for what they need it for.

Hmmm. He says it is an essential part of the curriculum.....

Hi all. A teacher has asked for pure Bromine, as opposed to Bromine water. This is teacher only, however he said he would demonstrate. Does anyone know where I would be able to source this? I can't seem to find anyone selling it.

Thanks!

Ah! Thanks bigmack! That's so much better! I was thinking this prac was quite scary as the initial concentration of Sodium Hydroxide that you need to make (100mL, which is eventually diluted down to 500mL) is 8M :w00t: . The first time the kids did it I walked into the classroom and none of them wer...

Hi all, A teacher wants to do "Chemical gardening" with his Year 11 Chemistry class. This is the method they are using: https://www.wikihow.com/Make-a-Chemical-Garden They have actually already done this, however some students were away and we have now run out of the Silica gel that they u...

Vaguely. I think it was kind of dismissed as too hard. I'm thinking about leaving this job soon though, so I think if they had to replace me they would replace with someone 5 days per week.

I just worked out our service factor (after figuring out what that was!) and it is 0.248! Although I do feel very busy (says me spending time here! :cheesy: ), I can't see it would need to be as high as 0.8. I would have nothing to do! And it's kind of my fault I am so busy as I was employed at 3 da...

Thanks for the advice! The two chemicals he mainly wants are $49 for 25g and $157 for 100mL. I think he will be using quite small amounts. He wants the students to make Methyl Orange (even though we have that already - he wants them to make it for the purpose of making it). I'll check with the head ...

I think in this case it is the teacher coming up with the chemicals. He has only started here this year, and comes from an industry background. When he said it's not crucial he meant that these specific chemicals are not crucial but he wants "something similar", whatever that means. He has...

Thanks. The head teacher is a bit clueless when it comes to Chemistry (he's a Physics teacher), so I was worried that he would just ask me what I thought if I asked him! But I'm leaning towards telling the chemistry teacher that if there is an alternative he should do that.

Hi everyone, One of my teachers has asked for a list of chemicals for some year 11 and 12 students for some kind of science extension project. I'm not sure exactly what for, as it is a new teacher and he's very vague. Anyway, none of the chemicals he wants are supplied by Westlab or any other chemic...

:blush2: We have one as our only fume hood. It was bought a few years ago because the in-built one didn't meet the safety standards in some way. I'm not sure exactly how. It is used very rarely in class, and I use it once every few weeks or so. I feel I would use it much more regularly if it was a b...

Thank you Rosalie. That's helpful

Hi Rosalie. Just wondering if you have had clarification on these points yet? Thanks