Using a simple A/B with vinegar, lye, and naphtha:

1.Many suggest to use approximately .6-1g of naphtha per gram of mhrb (powdered) in STB teks. Would this ratio remain the same for an a/b?

2. What are the suggested pH for the acid and base stages? So far reasoning suggests 3.5-4 and about 12 when basified.

3. If using pre-powdered mhrb, many teks state to multiply the water used by 1.5x or so. Just to be absolutely clear, would this multiply the amount of vinegar/lye/naphtha used as well?

4. Has anyone had glass break on them before from the exothermic reaction, even when done slow and proper? There is an extremely large brand new glass container laying can be used for mixing, like a giant cookie jar, but the stress of the reaction is raising red flags.

Thanks in advance for any help, its greatly appreciated

Oh and if anyone could clear up the sodium carbonate wash, thatd be great

1 - That should work just fine.

2 - You don't really need to measure your pH if you're using vinegar. You could use pure vinegar and be fine, but for economy's sake, 1:2 or 1:3 vinegar to water works well. For basifying, the pH needs to be at least 13, not 12. You don't need to measure this either. As you add the lye solution, your brew will go from deep clear red to milky grey/purple. Keep adding lye and the solution will clear again but the color will be a brownish black. Keep track of how much lye solution this took an add 25% more.

3 - It depends on the tek, but probably not since most A/B's start with a lot more water than STB's, employ multiple cooks, and call for straining the bark out of the solution before basifying. The reason you need more water for some STB's is that the bark/lye/naptha combination can form a sticky sludge that traps the naptha if the solution is too thick.

4 - Yes, glass can break. Usually it's more from the lye etching it than heat from the lye, but HDPE is much safer. Clumping cat litter comes in HDPE containers that are quite handy, and if things go horribly wrong, it's nice to have a bunch of cat litter around for cleaning up spills.

A final piece of unsolicited advice - don't throw anything away until you know you're done.

What's your question about the wash?

Should the Naphtha/spice solution be poured into a sep funnel, and then the sodium carbonate added or what? Theres a few different teks for this but which is the best?

Uh, sure?
That's about all there is to it.
Shake it up and separate.