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指出了铜与浓、稀硝酸反应实验的不足,介绍了铜与浓、稀硝酸反应的一体化微型实验装置、实验方法及实验优点。 相似文献
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由于铜与浓、稀硝酸的反应具有一定的危险性,故人教版高中化学必修Ⅰ并没有要求学生做此实验,铜与稀硝酸的实验装置和操作步骤都比较复杂,本文对铜与稀硝酸的反应实验进行改进,采用微型实验便于教师演示和学生自己实验,根据每一步的实验现象引导学生思考,培养学生的实验探究能力. 相似文献
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浓、稀硝酸氧化性不同,通过进行铜与浓、稀硝酸的反应实验现象及反应产物的对比实验,加强学生对不同浓度的硝酸氧化性不同的理解,同时增强学生的环保意识。 相似文献
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浓、稀硝酸氧化性不同,通过进行铜与浓、稀硝酸的反应实验现象及反应产物的对比实验,加强学生对不同浓度的硝酸氧化性不同的理解,同时增强学生的环保意识。 相似文献
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以废杂铜为原料,用浓硝酸浸出硝酸铜溶液,利用可控的封闭装置处理生成的NO2,减少其对大气的污染。用碳酸钠与硝酸铜溶液进行反应,反应温度为60~80℃,反应终点的pH=8.5左右,漂洗3次。通过元素分析、红外光谱分析、XRD等手段确定了该方法制备出高纯度的碱式碳酸铜。 相似文献
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Electron spectroscopy for chemical analysis (ESCA) has been employed to follow the surface nitration of cellulose papers in nitric acid–water and nitric acid–dichloromethane mixes with the aim of: elucidating the identity of the nitrating species in these mixes and from comparison of surface and bulk degree of substitution (DOS) further understanding on the role that morphology plays in the nitration of cellulose in these mixes. In nitric acid, nitric acid–water and nitric acid–dichloromethane mixes, surface nitration was observed to be slow (cf. to that reported in mixed acids) and the concentration of nitronium ion was observed to be low (cf. to mixed acids). On the basis of these observations and from the results of kinetic experiments, reported herein, it is proposed that the nitronium ion, NO2+, is the important nitrating species of cellulose in these nitric acid mixes. Nitration in all but the most concentrated nitric acid–dichloromethane mixes produced equal surface and bulk DOS; however, nitration in pure nitric acid produced different surface and bulk DOS. The latter result implies that the heterogeneous nature of the nitration reaction can influence the DOS achieved. 相似文献
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Hydrochloric and nitric acid treated apatite is not directly used as a fertilizer because of the hygroscopic character of the products. Another problem arises from the volatility of these acids and that acidulated product undergo reversions during drying with loss of the acid. We have found that apatite beneficiated with hydrochloric and nitric acids dried at an optimum temperature ~120°C has high available phosphorous. The products can be stored in the solid form in sealed polythene bags.Sumanasekara Chair in Natural Science 相似文献
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John D. Butler David M. Thorne 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1973,23(3):195-203
The analysis of nitric oxide, the principal nitrogen oxide in raw exhaust gas, is described by two different techniques. Concordance of analytical determinations using the Saltzman colorimetric solution method with the gas phase chemiluminescence method is demonstrated. By dilution of exhaust gas from an internal combustion engine with nitrogen it is shown that gas samples can be stored for periods of at least 30 min without significant change in sample composition with respect to nitric oxide. This procedure enables reliable estimations of nitric oxide in exhaust gas contained in a sealed transportable vessel to be performed at sites remote from the sample point, without introducing errors due to loss of nitric oxide by chemical reaction in the time between sampling and analysis. 相似文献
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利用热空气处理法和浓硝酸处理法分别对碳纤维(CF)进行表面处理,然后与尼龙(PA)12粉末按量比3∶7通过机械混合法制备PA12/CF复合粉末材料。将复合粉末材料进行注塑成型,考察了热处理温度及浓硝酸处理时间对复合材料力学性能和热性能的影响。结果表明,浓硝酸处理时间为1 h处理效果最好,与未处理的CF复合材料相比,注塑样条拉伸强度提高23%,弯曲弹性模量提高133%,维卡软化点提高6.2℃;扫描电子显微镜分析表明,经过热处理后的CF在PA12基体中分散均匀,两者的界面相容性良好。 相似文献