Nitrate de potassium

Chauyaku = RDX (Japan) 68 Cheddite = chlorate explosive (swiss) Chemecol blasting process 147 Chilesalpeter = sodium nitrate (german) 291 chlorate de barium 28 chlorate de potassium 262... 

As pointed out by E. E. Free, by using very dil. soln. of lead nitrate and potassium chromate—say M- to JH-soln.— yellow colloidal solutions are obtained which are stable for some days and, it glue be present, the soln. are stable for many months. J. Milbauer and K. Kohn also found that in the presence of acetic acid, or when boiled, the colloidal lead chromate is flocculated. F. W. 0. de Coninck observed that when crystalline lead chromate is boiled for one-half to one hoim... 

Pipette 25 mL barium ion solution (ca 0.01 M) into a 250 mL conical flask and dilute to about 100 mL with de-ionised water. Adjust the pH of the solution to 12 by the addition of 3-6 mL of 1M sodium hydroxide solution the pH must be checked with a pH meter as it must lie between 11.5 and 12.7. Add 50 mg of methyl thymol blue/potassium nitrate mixture [see Section 10.50(C)] and titrate with standard (0.01 M) EDTA solution until the colour changes from blue to grey. 

Pipette 25 mL of the bismuth solution (approx. 0.01 M) into a 500 mL conical flask and dilute with de-ionised water to about 150 mL. If necessary, adjust the pH to about 1 by the cautious addition of dilute aqueous ammonia or of dilute nitric acid use a pH meter. Add 30 mg of the xylenol orange/potassium nitrate mixture (see Section 10.50) and then titrate with standard 0.01 M EDTA solution until the red colour starts to fade. From this point add the titrant slowly until the end point is reached and the indicator changes to yellow. 

Pipette 25 mL of the solution containing magnesium, manganese and zinc ions (each approx. 0.02M), into a 250 mL conical flask and dilute to 100 mL with de-ionised water. Add 0.25 g hydroxylammonium chloride [this is to prevent oxidation of Mn(II) ions], followed by 10 mL of the buffer solution and 30-40 mg of the indicator/potassium nitrate mixture. Warm to 40 °C and titrate (preferably stirring magnetically) with the standard EDTA solution to a pure blue colour. 

Polarography has also been applied to the determination of potassium in seawater [535]. The sample (1 ml) is heated to 70 °C and treated with 0.1 M sodium tetraphenylborate (1 ml). The precipitated potassium tetraphenylborate is filtered off, washed with 1% acetic acid, and dissolved in 5 ml acetone. This solution is treated with 3 ml 0.1 M thallium nitrate and 1.25 ml 2M sodium hydroxide, and the precipitate of thallium tetraphenylborate is filtered off. The filtrate is made up to 25 ml, and after de-aeration with nitrogen, unconsumed thallium is determined polarographically. There is no interference from 60 mg sodium, 0.2 mg calcium or magnesium, 20 pg barium, or 2.5 pg strontium. Standard eviations at concentrations of 375, 750, and 1125 pg potassium per ml were 26.4, 26.9, and 30.5, respectively. Results agreed with those obtained by flame photometry. 

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