Experiments with Ash See FROMM, F., J. Chem. Educ., 24,231 (1947).
Potassium carbonate can be extracted from wood, charcoal, or tobacco ash. A procedure for the approximate determination of the quantity of potassium carbonate in a 0.1-0.2 gram sample of ash is given by Fromm, as well as a procedure for the extraction of this substance from a larger sample of ash and for the preparation of "potash soap." Questions:
The procedure for estimating the potassium carbonate content of ash is given, without explanation, in the article. Show that this procedure is, or is not, suitable for the estimation of the potassium carbonate content of an ash by determining the reactions that occur when the procedure is followed. Can you devise a procedure for determining potassium carbonate in ash whieh will yield a more accurate result? Ash is a heterogeneous material; hence, two different samples of ash, each weighing less than one gram, taken from a quantity of ash weighing several grams, might be expected to show marked
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differences in percentage composition. Devise a sampling procedure whieh will minimize the variation found in the compoeition of two or more different small samples. What other constituents of wood (charcoal) ash can you identify and measure quantitatively? Tobacco ash has a much higher percentage of potassium carbonate than charcoal ash, according to Frornm. What other compositional differences in these two kinds of ash can sou establish? Is it possible to identify different varieties of wood by quantitstive analysis of the corre~pondingashes for one, or perhaps two, constituents? Coal ash is quite different in appearance from wood ash. How different is i t in composition? Is there a difference between the ashes formed from bituminous and anthraoite coal? ( N o t e Students who undertake a study of this question and who find anthracite coal difficult to obtain may apply to one of us, J.A.Y., for a 50-gram sample of anthracite.)
