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Previous Next The best candle and soap tips online! TECHNICAL TREATISE ON SOAP AXD CASDLE3. ALKALIMETRY. 183 1 equivalent of potash = 47.11 grammes (1.6 ozs ) 1 ' of hydrate of pntaah = 50.11 " (1.96 " 1 ' of carbonate of potash = 60-11 (2.4 " 1 ? ' ' of soda = 31.00 (1.1 " 1 ' of hydrate of soda = 40.00 (1.4 " 1 1 of carl>onate of soda = 53.0(1 '? (1.8 " 1 ' 1 of cryslallized carb. of soda = M3.00 " (5 " 1 * of lime = 28.06 (O.»8 " 1 1 of hydrate of lime = 37.00 (1.2!) " 1 1 of carbonate of lime = 50.00 (1.75 " 1 cubic centimetre (0 27 fl. drrn.) of the nitric acid corresponds therefore with— 0.04711 gramme (0.737 grain) of potash O.OfSfiii (0.87 0,06911 (1.06S 0.0310 (0.43 0.0400 " (0.62 0.0530 " (0.83 0.1430 *' (2.21 0.0380 (0.43 0.0370 (O.r,? 0.05U0 (0.77 ) of hydrate of potash ) of carbonate of jxfl&sh ) of soda ) of hydrate of sod* ) of anhydrous carbonate of soda ) of crystallized caibonate of soda ) of lime ) (if hydrate of lime ) of carbonate of lime. The following ruble contains the quantities of base& in grammes, which are neutralized by 1 to 9 cubic centimetres (0.27 to 2.43 fl. drnis.) normal nitric acid. Il furnishes fur incidental calculations great assistance, since by the tenfold quantities the period needs only to be removed one space from riglit to left, while in the ca^e of tenth parts End hundredth parts the period should be removed one or two spaces from left to right; and the figures placed correctly under each other, and thus added:— 1 2 3 5 6 T S 9 11 fdrMe of pfftMh , 0.0.5611 0.11229 0.16S33 (1.28059 U.3W86 1.39277 Q. 41683 n.ioiss Cirb. of poUih 0.09911 0.13322 0.20733 O.a76« 0.3U-iS 0.414(8 U8377 O.5S2B3 i)£HB9 „,-(,„ Hydrate of aadn ....... O.PttO 0.080 0.1200 0.16C0 0.2000 0.2100 >.290O 0.3800 Aubydrouiotrb ofgoda (1.11630 0,1060 0.M9O 0.2120 D.2G.10 0.3160 J.371O 0.4240 0.1750 C.y.l. eftrb.fr •od..... 0.1*30 0.2480 0.4390 0.57^0 0.7150 0.6580 3.9010 1.0440 1.1870 0 213 Cirbonlte of lime 0.050 o.wo 0.150 0.208 0.250 9.300 J.350 0.400 0.150 If for instance by estimating a potash 8.75 cubic centimetres (2.3"i fluidrachnift) of normal nitric acid had been applied, it would be found by theohove table:— for 8.0 cubic centimeties 0.5528900 gr. li 0.7 " " 0.0483770" " 0.0a " " 0 0034555" Hence together, 0.6047125 " a calculation, which by multiplication of 0.069x8.75 war; found only a little more intricate. By the alkali metric test of lye we can operate in a double manner, either by measuring the equivalent in alkali or the combination of the same, which is the poiit in question; weighing them off in cubic centimetres, diluting if necessary with water, adding tincture of litmus or ti icfure of cochineal and titrating with normal uiiric acid. The cubic centimetres applied to the latter acid show immediately what per cent, contents of the alkali is contained in the lye. Or 10 cubic centimetres (2.7 luidraclmia) of the lye are placei by means of a pipette in a beaker and titrated as above described with normal nitric acid. Here, in 'order to find out the per cent, contents, the applied cubic cent metres of i-itrio acid must be multiplied by the equivalents of the alkali, or by the combination of the same. The result is in both cases the same, only that in the Utter mode of proceeding a multiplication becomes still necessary. If, for example, of a caustic lye 3.1 cubic centimetres (0.8 fluidrauhms) had been transferred by means of a pipette, and for its neutralization 2.6S5 cubic centimetres normal nitric acid hail been used,then this lye contains 2.635 per cent, of caustic sola. If 10 cubic centimetres (2.7 fluidraahms) lye lmd been measured off,then they weuld have required 8.o cubic ccntinetrea (2.3 flui- drachma) nitric acid for their neutralization — ?-—— 0.2635; in 100 parts hence 2.635 aa in the first example. If the lye had to be investigated as to its contei ts of hydrate of soda, then 4.0 cubic centimetres (1.08 flu id rashm) would have lmd to be measured off, and the same with soda 184: TECHNICAL TREATISE ON SOAP AND CANDLES. ALKALIMETRY. 185 or anhydrous carbonate of soda, 5.3 cubic centimetres (1.43 flnidrachm), and in the case of crystallized carbonate of snda 14.3 cubic centimetres (3.8(3 fluidrachms). In that case the respective quantities of normal nitric acid used would Lave been 3.40 cubic centimetres (0.90 fluidracbm), 4.505 cubic centimetres (1.2a fluidr;ichm), arid 12.155 cubic centimetres (S.'IS fluidrachms), so that the same contains 3.40 per cent. hydrate of soda, 4.505 per cent, anhydrous, and 12.o5 per cent, crystallized carbonate of soda. NURMAL ALKALI. As luis already been mentioned above, it is in many cases serviceable to have on hand an alkaline liquid wind: is equivalent :o the normal nitric acid. For such purpose a pot ash} a soda, or an ammonia, solution may serve. The latter is preferable to either of the other two. Ammonia can be obtained in commerce in an almost pure state, under the name of water of ammonia, and can be bought in any drug store. It, absorbs less carbonic acid from the ai*, and hence keeps unaltered for a longer period. Some little ammonia may indeed evaporate; but since we have normal nitric acid on hand, this litre may be corrected at any moment. Meanwhile there is not much fear of (lie evaporation of ammonia from such a diluted liquid as the normal alkali :a, as it only holds 1.7 per cent, of anhydrous ammonia. To prepare normal alkali, the commercial water of ammonia is used, which contains about 10 per cent, of ammonia; this, diluted with four times its weight of wxter, gives a liquid which approximates to the correct tit re, 1 7 per cent., but it is somewhat stronger. To correct this, take 10 to 20 cubic centimetres {2.TO to 5.40 fluidrachms) nitric acid in a porcelain ci;p, color with tincture of litmus bright red, and titrate with ammonia until a pure blue color ensues, In proportion as less of the ammonia has been used than 10 or 20 cubic centimetres (2.70 to 5.40 fluidrachms) the first mixture is diluted with distilled water. For instance we bad 125 grammes (4.40 ozs.) uramonia diluted with J kilogramme Previous Next
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