由于硫脲与硫氰酸銨的熔融混合物中,除较难分离的硫脲与硫氰酸根外,还有熔融副产品如硫、硫化物与胍等均足影响分析。因此用碘量法測定硫脲,以及硝酸銀或硝酸汞測定硫氰酸根均不易获得較准确結果。所以前人测定熔融混合物的結果不一致。我們将此反应控制在±0.1°的甘油浴內,采用极譜法以确定平衡熔融混合物的組成。 As the thiourea and ammonium thiocyanate melt mixture, in addition to the more difficult to separate the thiourea and thiocyanate, as well as the melting by-products such as sulfur, sulfide and guanidine and other foot effects analysis. Therefore, iodine determination of thiourea, and silver nitrate or mercury nitrate determination of thiocyanate are not easy to get more accurate results. So predecessors determine the results of the molten mixture is inconsistent. We control this reaction in a ± 0.1 ° glycerol bath and use polarography to determine the composition of the molten mixture.