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Saerynide
National Hazard
Posts: 954
Registered: 17-11-2003
Location: The Void
Member Is Offline
Mood: Ionic
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For the American Weigh scales, Ive tried both:
American Weigh DIA-10 Digital Carat Scale 50x0.01ct / Milligram: http://www.americanweigh.com/product_info.php?cPath=60&p...
and
American Weigh Gemini-20 Portable Milligram Scale 20x0.001g: http://www.americanweigh.com/product_info.php?cPath=60&p...
For My Weigh, Ive tried My-weigh GemPro50 Jewelry Scale: http://balance.balances.com/scales/870
All 3 times, I had to send them back to the seller. Maybe their larger capacity scales will be more accurate and precise, but I can vouch for sure to
stay away from their mini scales - they have no accuracy or precision.
Several times, I've tried putting 3-4 mg of material on them and they will often register nothing. The American Weigh ones were so ridiculous as to
measure the calibration weight wrong every time even after calibration (I had previously measured the weight in my research lab to the 0.1 mg, so I
know what it *should* weigh).
"Microsoft reserves the right at all times to monitor communications on the Service and disclose any information Microsoft deems necessary to...
satisfy any applicable law, regulation or legal process"
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Stifle
Harmless
Posts: 20
Registered: 7-12-2008
Location: Salt Lake City Utah
Member Is Offline
Mood: Hopefull
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that sounds pretty bad. accuracy would be top of the list on my priorities for these scales so I guess ill have to find some other brands to use.
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zed
International Hazard
Posts: 2283
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
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Burets appear to be overpriced. Want to do some titrations? Use disposable syringes.
They are graduated, easy to control, hard to damage, and are very inexpensive. If you are concerned about the pointy ends of the needles, just cut
them off.
Syringes work equally well, as graduated cylinders.
Burets and other chemical glassware/plasticware are specialty items. Naturally spendy.
Disposable syringes are not specialty items, they are produced in all sizes, on a vast scale. Diabetic supply companies/clubs sell them dirt cheap.
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Lambda-Eyde
National Hazard
Posts: 860
Registered: 20-11-2008
Location: Norway
Member Is Offline
Mood: Cleaved
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Zed: I think a school easliy can afford burets, and IMO they are superior to plastic syringes when it comes to titrations. There's a reason
professional labs don't use syringes, you know. 
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undead_alchemist
Hazard to Others
Posts: 189
Registered: 12-1-2007
Location: Vancouver, Canada
Member Is Offline
Mood: Tired, Cleaning up corporate messes at work!
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The company that I work for has pretty good prices on both ASTM Class A, and ISO DIN Class B Burettes.
How about a micro scale 1ml, 2ml or 5ml Class B??..
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zed
International Hazard
Posts: 2283
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
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No point in spending big bucks on burets for a high school chem class. Cheaper is better.
Ideas are the important thing, not pin-point accuracy.
My experience with burets at the college level was that they were extremely mortal. They are long, awkward, and fragile. Easy to break and expensive
to replace. Students would break them, then be aghast at having to pay the high replacement cost. The presence of a stopcock sends the price
soaring.
In simpler times, to keep costs down, many schools used burets that had a nipple at the bottom end. Slip a piece of latex tubing over the nipple,
stick a tightly fitting glass bead inside the latex tubing, then insert a piece of finely pointed glass tubing at the bottom.
Squeezing at the bead, buckles the latex tubing and allows liquid to flow. Stop squeezing, and the tubing snaps tight again. Just as accurate as a
stopcock, at a vastly lower price.
[Edited on 17-12-2008 by zed]
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dapper
Hazard to Self
Posts: 66
Registered: 8-11-2006
Member Is Offline
Mood: No Mood
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oldwillknott.com for scales - great prices, fast shipping
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nitric
Harmless
Posts: 40
Registered: 18-8-2008
Member Is Offline
Mood: nitrous
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as for heating if you would be allowed(lack of natural gas lines) use propane tanks, easily you could set up them and they would be refillable, even
though electric is good for most applications in a lab, it would at least be on hand if Bunsen burners were needed
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orbit_research
Harmless
Posts: 2
Registered: 6-1-2009
Member Is Offline
Mood: No Mood
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I am selling some Jones reagent- great for visual aid for changes in oxidation states Cr(VI) red to Cr(III) green
see ebay item 190281558976
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