Search found 1191 matches

by Merilyn1
02 Jul 2024, 13:32
Forum: Safety with Chemicals
Topic: High Voltage power supply Risk Assessment
Replies: 3
Views: 1003

Re: High Voltage power supply Risk Assessment

Was this an induction coil? We have limited the use of ours and bought the spectrum tube power supply units made by IEC. Wasn't I happy about that purchase! The physics teachers still use the induction coil for the other things such as maltese cross etc. Sorry - can't help you with a specific risk a...
by Merilyn1
27 Jun 2024, 09:47
Forum: Recipes and Pracs
Topic: Biurets reagent
Replies: 7
Views: 3138

Re: Biurets reagent

I've always given it out as the two separate chemicals. I'd never thought of pre-mixing.
The teachers here have sometimes order 0.5M NaOH and 1% copper sulfate. I'm guessing it works okay and the lower concentration of NaOH is a safer option.
by Merilyn1
27 Jun 2024, 09:08
Forum: Announcements
Topic: Hanging up my lab coat
Replies: 2
Views: 831

Hanging up my lab coat

Hi All After lots and lots of consideration, deep thought and prayer, I have decided to hang up my lab coat one last time and step down from my labbie job here at Wollondilly Anglican (Tahmoor NSW). I will be focussing on my WHS role. Means I'll be here two days a week and I'll be going back to my h...
by Merilyn1
19 Jun 2024, 14:00
Forum: Sourcing Materials & Eq Repairs
Topic: Brains, hearts, kidneys & plucks
Replies: 23
Views: 11957

Re: Brains, hearts, kidneys & plucks

Where are you located? Im located in Western Sydney NSW. I have found a place that supplies eyes and hearts however I am still in need of liver's and kidney's. Thank you :) I would think kidneys and liver to be easier to source than eyes and hearts! I get ours from our local butcher. I do have to g...
by Merilyn1
19 Jun 2024, 13:58
Forum: Recipes and Pracs
Topic: sodium thiosulphate - and HCL
Replies: 14
Views: 3588

Re: sodium thiosulphate - and HCL

Handling toluene or hot NaOH may not be worth the outcome. It probably works but sounds toxic. Toluene is pretty nasty.
Not sure in this case if it would work, but Napisan gets a fair old use in most school prep rooms for cleaning glassware.
by Merilyn1
17 Jun 2024, 12:12
Forum: Chemistry and Labware - General
Topic: Cleaning Glassware Fast!
Replies: 25
Views: 2327

Re: Cleaning Glassware Fast!

The Chem has always done this as a demo for the whole class. Uses bromine water but one set up, always in the fume hood.
by Merilyn1
17 Jun 2024, 09:41
Forum: Chemistry and Labware - General
Topic: Cleaning Glassware Fast!
Replies: 25
Views: 2327

Re: Cleaning Glassware Fast!

Marama T wrote: 17 Jun 2024, 08:15 Don't bromine water, cyclohexane etc. have to be used in a fume cupboard? How will that happen? This prac is ridiculous.
A very good point!
by Merilyn1
11 Jun 2024, 15:06
Forum: Chemistry and Labware - General
Topic: Cleaning Glassware Fast!
Replies: 25
Views: 2327

Re: Cleaning Glassware Fast!

It might also be worth checking with the teacher that the request is correct and they don't mean 60 total for the 10 students, not 60 each. That sounds excessive! I agree. Get the teacher to clarify as it does seem excessive. But sometimes teachers think we can perform miracles. I mean, I know I'm ...
by Merilyn1
06 Jun 2024, 14:04
Forum: Chemistry and Labware - General
Topic: Distilled water, lead nitrate and chloride ion contamination
Replies: 4
Views: 552

Re: Distilled water, lead nitrate and chloride ion contamination

You could also search on Science Assist. You can post questions but need to have paid the subscription. I always get really good, clear technical advice from them. It frightens me that DofE schools are being told to abide by such outdated information. Not only are they exposing students to the known...
by Merilyn1
06 Jun 2024, 10:53
Forum: Chemistry and Labware - General
Topic: Distilled water, lead nitrate and chloride ion contamination
Replies: 4
Views: 552

Re: Distilled water, lead nitrate and chloride ion contamination

I can't help with reason for the cloudiness and things leaching from bottles, but I am concerned about students using 0.1M lead nitrate. Riskassess does not recommend this concentration for students any more. We buy our distilled water in 20L drums. When I send it out to classes, I have some empty, ...
by Merilyn1
03 Jun 2024, 13:52
Forum: Safety with Chemicals
Topic: Length of Chemical Storage
Replies: 20
Views: 9666

Re: Length of Chemical Storage

Are you able to talk to your compliance people? They may not understand the longevity of chemicals in schools. As long as they are safe, which most things would be, there would be no WHS reason for disposing of them. They may be getting caught up with pesticides that do have a shelf life and thereaf...
by Merilyn1
03 Jun 2024, 07:40
Forum: Chemistry and Labware - General
Topic: Cleaning stock bottles
Replies: 5
Views: 842

Re: Cleaning stock bottles

Currently my flammables cabinet is too small to store them - especially since I realised it is missing the bottom shelf and items are sitting in the base of the cabinet. What is shocking about this, is I've been looking at it for six years and it hadn't registered... Anyway, I've also never had a pr...
by Merilyn1
31 May 2024, 14:27
Forum: Chemistry and Labware - General
Topic: Cleaning stock bottles
Replies: 5
Views: 842

Cleaning stock bottles

The previous labbie used to decant the organics for Senior Chem into smaller stock bottles to send out to class - so all the fun ones, hexane, hexene etc. I can't see the point of this. I just send out the bottle it comes in. Chemistry is the only subject that ever uses it so I don't see why I shoul...
by Merilyn1
31 May 2024, 10:06
Forum: Sourcing Materials & Eq Repairs
Topic: hoses for condensors
Replies: 4
Views: 665

Re: hoses for condensors

Still using rubber tubing here. It's the cheapest option, easy to source, can cut it to the length you need. It seems to do the job, ie never had any failures with it.
by Merilyn1
30 May 2024, 12:17
Forum: Sourcing Materials & Eq Repairs
Topic: ammeters / voltmeters
Replies: 12
Views: 2604

Re: ammeters / voltmeters

Ouch - we have the IEC ones but didn't pay $120 for them, maybe $80? Anyway, that doesn't help you now. Consider the cost of the analogue ones and how quickly they fail. The IEC ones seem really durable, we have had them a couple of years and had no problems with them. Teachers love them. They seem ...
by Merilyn1
27 May 2024, 12:10
Forum: Sourcing Materials & Eq Repairs
Topic: Glass tubing
Replies: 25
Views: 2283

Re: Glass tubing

Yeah, Haines, Science Supply Australia can help. There are also capillary tubing sets that come with capillary tubing with different internal diameters - all cut and ready to go with bungs. I had a teacher show me once how to make very thin capillary tubing from glass pipettes. I ended up with more ...
by Merilyn1
24 May 2024, 09:48
Forum: Biology, Physics...
Topic: Agar plates - how old is too old?
Replies: 9
Views: 1624

Re: Agar plates - how old is too old?

I've chucked a couple of them into the incubator. Waiting to see the "magic"!
by Merilyn1
23 May 2024, 14:56
Forum: Biology, Physics...
Topic: Agar plates - how old is too old?
Replies: 9
Views: 1624

Re: Agar plates - how old is too old?

Thanks guys! Good to have back up to my thoughts. It's Year 10, not like they're working on a PhD.

I'm waiting to see the nose of the teacher get turned up!
by Merilyn1
23 May 2024, 14:24
Forum: Biology, Physics...
Topic: Agar plates - how old is too old?
Replies: 9
Views: 1624

Agar plates - how old is too old?

Just reaching out to see what your thoughts are on how old is too old for an agar plate? Long story (maybe it should be in the "just a whinge" section). Ext Science student asked for a heap of plates. Year 12 Bio teachers also asked for heaps. Ext Sc student used 10 then dropped the subjec...
by Merilyn1
21 May 2024, 11:03
Forum: Biology, Physics...
Topic: standardisation of NaOH
Replies: 13
Views: 5240

Re: standardisation of NaOH

LOL! I get worried about giving some teachers conc HCl.