Day: June 5, 2014

Thursday, 5 June 2014

08:07 – Public schools have been in the news here lately. With the Republicans firmly in control of state government, big changes to public education are in prospect.

Legislators are doing their best to do away with tenure for public school teachers. That suffered a setback recently when a liberal judge ruled that the state couldn’t take back something that had already been granted. I expect the state supreme court will reverse that decision. And North Carolina is withdrawing from Common Core, which the state just began implementing recently. A review panel has been set up, tasked with adopting new state curriculum standards, with the provision that Common Core is not acceptable even if the panel determines that it is the best available alternative. And legislators have carefully crafted a new law to get around US Supreme Court decisions on restricting religion in public schools.

The real problem is that the politicians have set their sights far too low. The fundamental problem is public schools, period. The North Carolina constitution requires the state to provide an elementary through high school education to all children. But the constitution doesn’t specify how that is to be done.

The solution is to establish an educational voucher system. A real one, one that is available to all students’ families rather than just a tiny percentage. And one that is funded directly by the pool of money allocated to public education. Those vouchers should be for the amount the state currently spends per student, and the amount of any voucher redeemed at a private school should immediately be deducted from the budget allocated to the public schools in that student’s district.

It’s also important that the state implement absolutely no requirements or standards for private schools, including any restrictions or requirements concerningn secular versus religious, teacher certifications, and so on. It should be entirely up to the private schools themselves to set their own policies and to the parents and students to decide what constitutes an appropriate education.

The immediate result of such a true school choice program would be that public schools would have to compete efficiently and effectively in an educational free market if they want to survive at all. Most would not, and that’s all to the good. Would some students receive very poor educations? Of course they would, but almost certainly fewer than currently receive very poor educations in our existing public schools.


15:05 – I’ve been making up solutions and filling bottles all day, hundreds of bottles. And I just got to the next item on my to-do list, which is methyl red solution. Methyl red, AKA 2-(N,N-Dimethyl-4-aminophenyl)azobenzenecarboxylic acid, is extraordinarily insoluble in water. So much so that the solution we use, 0.02% w/v, exceeds the solubility of methyl red. That’s 0.2 g/L. If I simply add 0.2 g of methyl red to a liter of water, about 90% of it (at a guess) remains undissolved.

Fortunately, there’s a way around this. The sodium salt of methyl red is considerably more soluble than the free acid. Unfortunately, I wasn’t thinking about that when I ordered what amounts to a lifetime supply of the free acid. So I need to convert the free acid to the sodium salt. That’s easy enough to do: simply dissolve the methyl red free acid in a (very) dilute solution of sodium hydroxide to form a solution of sodium methylredate. (I lay claim to creating that anion name; Google finds zero instances of it.)

Just how dilute? Well, the stoichiometry says that one mole of sodium hydroxide reacts with one mole of methyl red. The molecular mass of the free acid is 269.30 g/mol, while that of sodium hydroxide is 39.9971 g/mol. But making up a liter of 0.02% methyl red requires only 0.2 g, or 0.00074+ mole. Accordingly, for a 1:1 correspondence, I need about 29.7 milligrams of sodium hydroxide. The standard 6 M sodium hydroxide solution that we supply with many of our kits contains 240 mg/mL, so I’d need to add about an eighth of a milliliter of that solution per liter. The plastic pipettes we buy 10,000 at a time deliver about 33 drops/mL, so call it four drops.

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