Chromic said: 100g of 25% NaOH is 25g of NaOH and 75g (75mL) of water. So the solution, which weighs 100g is 25% NaOH.
Thanks very much all. Very helpful. Nope, I don't know what hygroscopic means, but then I'm learning and wouldn't dream of dreaming unless I knew that and a whole lot more. So, on with the questions...
what specifically do w/w, w/v, and v/v mean? Chromic, you say that w/w is the most common. Is w/w (i.e. 5g NaOH + 95g dH2O = 100g 5% NaOH soln.) the mixing method to be used in most (all?) of the rxn's here? How about specifically for the benzo-meoh-wacker? Under what circumstances would someone choose one method over another (It's almost like you're taking an exam, eh? Except of course you're the instructor )?
Thanks,
greeter