Search found 403 matches
- 20 Mar 2018, 12:57
- Forum: Recipes and Pracs
- Topic: Sucrose Test with Benedicts
- Replies: 3
- Views: 3687
Re: Sucrose Test with Benedicts
Thank you! Very interesting Our TCE Bio kids do a banana prac every year (leave green bananas for a week and test with Benedict's and iodine throughout) and we never get very good results. It basically goes from negative to a wishy washy positive with no graduation of colour. Did you manage to get i...
- 20 Mar 2018, 12:53
- Forum: Chemistry and Labware - General
- Topic: Life span of Sodium Hydroxide
- Replies: 5
- Views: 4970
Re: Life span of Sodium Hydroxide
I keep mine for longer then 3 months...although it does not hold its molarity long. If I need standardised naoh I re standardise if it is only than a month or so. Mine is stored in whatever I have on hand. Molten NaOH will dissolve glass so I suppose in soution it may have some effect but I have nev...
- 20 Mar 2018, 08:19
- Forum: Sourcing Materials & Eq Repairs
- Topic: spectrum tubes
- Replies: 9
- Views: 7123
Re: spectrum tubes
We have some old ones similar to the top one in your pictures and newer ones like the bottom one. Our newer ones are from Cider House Tech (we get all our pasco gear from there) Never had a complaint about them.
- 20 Mar 2018, 08:06
- Forum: Miscellaneous
- Topic: Notice for experiments?
- Replies: 8
- Views: 7208
Re: Notice for experiments?
Depends. We say 48 hours but in reality 24 is usually fine. We say a week if something needs to be brought in, but in reality 48 hours is usually fine. With my IB students who all do individual research projects for ever subject I say a week, 2 if I need to order stuff online. In my new job I have n...
- 16 Mar 2018, 14:20
- Forum: Safety with Chemicals
- Topic: When does a risk assessment need to be done?
- Replies: 26
- Views: 13754
Re: When does a risk assessment need to be done?
Me againnnnnnnnnnnn! anybody have a teacher doing chemistry practicals with only a few children not entire class after school hours. When rest of the department has gone home for the day/weekend. Being a little proactive instead of reactive lol. Well it's going to be reactive, have passed on furthe...
- 09 Mar 2018, 13:37
- Forum: Chemistry and Labware - General
- Topic: Pasco WiFi pH sensors - buffer solution
- Replies: 7
- Views: 6518
Re: Pasco WiFi pH sensors - buffer solution
I usually just wack it on the magnetic stirrer and leave it for a while. It eventually dissolves (That's my default with most things, then I add heat if it's not dissolving or leave overnight)
- 09 Feb 2018, 10:48
- Forum: Chemistry and Labware - General
- Topic: Finding the unknown solution
- Replies: 10
- Views: 4940
Re: Finding the unknown solution
I do this all the time (senior chem) Basically I put all the information on the label except name and formula. Multiple unknowns get labelled with unique identifiers for each, teacher gets SDS for each chemical. So no different to putting any chemical out in the lab really.
- 09 Feb 2018, 10:41
- Forum: Safety with Chemicals
- Topic: whole school chemical audit
- Replies: 19
- Views: 9278
Re: whole school chemical audit
Plus depending on your phone, some files won't download properly or at all. That's why we stick to paper copies as well, although I do have them electronically and provide links on our register.
- 07 Feb 2018, 11:00
- Forum: Safety with Chemicals
- Topic: whole school chemical audit
- Replies: 19
- Views: 9278
Re: whole school chemical audit
Samantham, how do they get around that fact that an manufacturers SDS has to be available to all workers at the site of chemical usage and storage? Does everyone have access to a phone or computer and internet? I hate Chemwatch and have moved away from using it. The school only pays a bit over $100 ...
- 05 Feb 2018, 11:30
- Forum: Safety with Chemicals
- Topic: whole school chemical audit
- Replies: 19
- Views: 9278
Re: whole school chemical audit
Thanks Labbie. The trouble is I am starting from scratch. So besides science there is nothing from last year! This is part of the problem. As much as my direct manager in this area doesn't want me to, I am going to have to start physically going and starting the process myself in some departments. W...
- 05 Feb 2018, 08:04
- Forum: Safety with Chemicals
- Topic: whole school chemical audit
- Replies: 19
- Views: 9278
Re: whole school chemical audit
We have a Chemical Safety Manager employed one day a week to do this. That person happens to be me :D I have s part timer come in and do lab work for me on a Friday so I can do all the chem safety stuff. ....well that's how it is meant to work anyway. I don't physically do the audits/compile lists. ...
- 01 Feb 2018, 08:10
- Forum: Biology, Physics...
- Topic: Elodea alternative
- Replies: 11
- Views: 10982
Re: Elodea alternative
I didn't know it was only in Vic you could get it! (Southern biological) We have a pond on site where we cultivate a few *cough* maybe not quite legal biosecurity wise *cough* . I inherited it but it is super handy.
- 14 Dec 2017, 10:36
- Forum: Sourcing Materials & Eq Repairs
- Topic: LPG Bunsen Burners
- Replies: 2
- Views: 2020
Re: LPG Bunsen Burners
Natural gas burners have a larger aperture due to the lower pressure so that is why they burned so well using LPG! It sounds like a pressure or air mix issue.
- 14 Dec 2017, 10:33
- Forum: Biology, Physics...
- Topic: Radiation sources
- Replies: 21
- Views: 14154
Re: Radiation sources
We store ours in a locked metal box in a locked cupboard in the physics lab (which is locked when not in use)
- 14 Dec 2017, 10:08
- Forum: Safety with Chemicals
- Topic: Risk Assess archiving
- Replies: 3
- Views: 2804
Risk Assess archiving
Does anyone know if you can easily archive from the risk assess program in bulk? e.g. not just saving every RA individually
- 06 Dec 2017, 11:07
- Forum: Biology, Physics...
- Topic: IB pracs
- Replies: 1
- Views: 4091
Re: IB pracs
Here are some of the titles from my yr 12 IB IA's this year: Effect of ethanol concentration of yeast respiration How does the pH of water affect the germination rate of hydroponically grown lettuce (latuca sativa) Antimicrobial effect of Thymol Does cellulase affect the concentration of betalaine p...
- 29 Nov 2017, 12:56
- Forum: Recipes and Pracs
- Topic: Iodine Clock Reaction
- Replies: 6
- Views: 7211
Re: Iodine Clock Reaction
Yes, both solutions were clear. It sounds like the starch isn't dissolving if it is cloudy. Maybe try putting the acid in solution B and see if that works?
- 29 Nov 2017, 11:39
- Forum: Recipes and Pracs
- Topic: Iodine Clock Reaction
- Replies: 6
- Views: 7211
Re: Iodine Clock Reaction
I did this last week. It worked perfectly. The recipe was slightly different to yours though:
Solution A:
4.1g Sodium Acetate
0.6g soluble starch
50g KI
9.4g sodium thiosulphate
1L water
Solution B:
30ml Glacial acetic acid
500ml 3% H2O2
470ml water
Solution A:
4.1g Sodium Acetate
0.6g soluble starch
50g KI
9.4g sodium thiosulphate
1L water
Solution B:
30ml Glacial acetic acid
500ml 3% H2O2
470ml water
- 29 Nov 2017, 11:33
- Forum: Safety with Chemicals
- Topic: RiskAssess chemical codes
- Replies: 42
- Views: 17917
Re: RiskAssess chemical codes
Borax was one of those chemicals that got reclassified under the GHS. It's hazardous rating dramatically increased, hence the teacher only classifications. It now has a fertility warning hazard code (H360). RiskAssess is the most up to date information.
- 24 Nov 2017, 07:37
- Forum: Recipes and Pracs
- Topic: Christmas themed prac's for yr6 visits
- Replies: 14
- Views: 7208
Re: Christmas themed prac's for yr6 visits
sorry to burst the Christmas BAUBLE ... but NO BORAX for year 6 ... maybe a demo of elephant toothpaste with red and green food colouring .. We allow borax for slime making but gloves must be used and no taking home the product. Kids are not allowed to use it in powdered form. A borax solution less...