A general discussion and Q & A forum.
Labbie
Posts: 3247 Joined: 28 Nov 2006, 10:00
Job Title: Retired
Suburb: At Home
State/Location: NSW
Post
by Labbie » 09 Nov 2007, 11:03
One lovely teacher, has some burnt sugar in our new test tubes, about 22 of them. Any ideas how to remove this mess
I have tried really HOT HOT water, & soaked over night with oxalate acid. Help
Regards Labbie
Lab Manager/Lab Tech, mind reading etc etc
Now retired
RosalieM
Posts: 1795 Joined: 20 Mar 2007, 10:00
Job Title: Lab Assistant
Suburb: Tamworth
State/Location: NSW
Post
by RosalieM » 09 Nov 2007, 11:12
Haven't had to deal with that problem, but bi-carb soda or napisan seems to work for just about anything. Worth a shot! Good luck
Rosalie
Ocean Breeze
Posts: 798 Joined: 01 Jun 2006, 10:00
Job Title: Lab Manager
State/Location: NSW
Post
by Ocean Breeze » 09 Nov 2007, 11:46
just soak them is some Na OH overnight. They will just rise clean in the morning! No scrubbing required
Lyn
Posts: 706 Joined: 16 May 2006, 10:00
Job Title: Lab Assistant (Technician)
School: St. John's Catholic College
Suburb: Darwin
State/Location: NT
Post
by Lyn » 09 Nov 2007, 12:36
What strength NaOH would you recommend? I have several evaporating basins with charred remains from a jelly crystal prac which no amount of scrubbing is moving.
dime
Posts: 703 Joined: 13 Jun 2007, 09:55
State/Location: NSW
Post
by dime » 09 Nov 2007, 13:13
1M or 2M max NaOH should do the trick. It will loosen just about anything. Even melted (sublimed?) sulfur from test tubes or deflagrating spoons. Might need to leave them for a couple of days, just keep soaking till the stuff lifts off. Have a nice weekend all :
Labbie
Posts: 3247 Joined: 28 Nov 2006, 10:00
Job Title: Retired
Suburb: At Home
State/Location: NSW
Post
by Labbie » 09 Nov 2007, 13:20
I had forgotton about Nappy Sand, Silly me, but we have run out of that. So I will have a go with Sodium Hydroxide, I have some Old 3M which I could use up, as a cleaning Acid. Thank you again
Regards Labbie
Lab Manager/Lab Tech, mind reading etc etc
Now retired
ellice
Posts: 193 Joined: 27 Jul 2007, 15:29
Job Title: Lab technician
School: The Illawarra Grammar School
Suburb: Figtree
State/Location: NSW
Post
by ellice » 09 Nov 2007, 13:46
We keep a stock of small test tubes (7x1cm) for burning sugar. Then I just throw them away!
Labbie
Posts: 3247 Joined: 28 Nov 2006, 10:00
Job Title: Retired
Suburb: At Home
State/Location: NSW
Post
by Labbie » 11 Nov 2007, 18:21
Yes so do I, but this teacher helped him self. He did'nt ask, just went ahead and did it.
That Nappy San is really good.
Last edited by
Labbie on 11 Nov 2007, 18:21, edited 1 time in total.
Reason: spelling
Regards Labbie
Lab Manager/Lab Tech, mind reading etc etc
Now retired