Sunday, 25 January 2015

09:49 – Barbara is bound and determined to clean house today. While I was walking Colin, she cleaned toilets, even though I’d told her just before I left that I’d do that when I got back. I managed to get the kitchen floor vacuumed before she showed up and demanded that I hand it over. So she’s now vacuumed the den, worked her way down the hall, and into our bedroom and bath.

I’m currently oven-drying some nominally anhydrous magnesium sulfate. The problem with this stuff, like anhydrous calcium chloride, is that it sucks water vapor out of the air. If you pour either one into a weigh boat on a scale and watch the indicated mass, you can actually see it increasing as the solid sucks water out of the air. So I dry it at 300C, fill and pack bottles while it’s still quite warm, and tape the caps. I’ll make an extra bottle, date it, and weigh it on a milligram balance. The last time I did that, it gained only about 0.5% mass in a year, but as soon as the bottle is opened it’ll start sucking up water vapor until the mass of the solid nearly doubles.

This is part of an order that came in Friday from one of our state virtual school customers that provides AP chemistry materials for distance-learning to state residents. I need to get the stuff finished and packed up today so that I can ship tomorrow.