Word of warning to those ordering this via Amazon: I did too - and was sent hydrophobic fumed silica, even though it was clearly sold as "Aerosil 200" (which is hydrophilic). Cabosil now in hand, I may be able to try again soon...
Moral of the story: stick with Bostick & Sullivan.
difference in price is 500ml (1/2 Qt)for 19.00 from B&S and Amazon is $12.00 for 5 Qts. I'll take the risk I can order a whole lot of times before I would be loosing my money.
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