Organic 2 Review Problem 289

Organic 2 Review Problem 289 - P REPARATIONS 273 this p...

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PREPARATIONS 273 this purpose. Now add powdered sodium bicarbonate* (about 30 g.) in small quantities at a time with stirring until the evolution of carbon dioxide is complete, and the solution is just alkaline to litmus-paper: during this operation keep the temperature of the mixture between 5 5°and 6o°. Now remove the basin from the sand- bath and cautiously add 24 g. of powdered potassium cyanide,! continuing the stirring both during and after the addition. The temperature of the mixture rises spontaneously after the addition is complete and the cyanide rapidly dissolves. When the tem- perature of the well-stirred mixture reaches 90-95°, a vigorous effervescence usually occurs for a few seconds and then rapidly subsides. When this reaction is over, replace the basin on the sand-bath and heat gently, meanwhile stirring the brown solution with the thermometer until the temperature reaches 135° (about 30 minutes' heating is usually required). Maintain the tempera- ture at 135° for a further 5 minutes, and then remove the basin
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.

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