论文部分内容阅读
操作方法: 准确称取试样2.000g于300ml烧杯中,加入浓盐酸60ml,低温加热溶解.取下冷却,加入10m150%柠檬酸溶液,然后边搅拌,边缓缓加入氨水,使pH=5～6。再加入10%硫酸钾溶液20ml。静置,待溶液澄清后即用中速滤纸过滤。再用水洗涤沉淀,直至将Fe~(3+)洗净(用硫氰化铵检验)。再将沉淀连同滤纸移入已恒重的瓷坩埚中,加盖,置于高温电炉上灰化,最后再于800℃马弗炉中灼烧半小时,称重。计算:Ba=(W_2-W_1)×0.5884)/200)×100%注:(1)试样宜用浓盐酸溶解,不宜用1+1盐酸,否则溶解比较困难。温度也不宜过高,否则盐酸
Method of operation: accurately weighed sample 2.000g in 300ml beaker, add concentrated hydrochloric acid 60ml, low temperature heating to dissolve.Remove cooling, add 10m150% citric acid solution, and then stirring, while slowly adding ammonia to pH = 5 ~ 6. Then add 10% potassium sulfate solution 20ml. Let stand until the solution is clarified with medium-speed filter paper to filter. The precipitate was washed again with water until Fe ~ (3+) was washed (checked with ammonium thiocyanate). The precipitate and the filter paper are then transferred to a constant weight porcelain crucible, stamped and placed in a hot electric furnace to be ashed, and finally burned in a muffle furnace at 800 ° C for half an hour and weighed. Calculation: Ba = (W_2-W_1) × 0.5884) / 200) × 100% Note: (1) The sample should be dissolved with concentrated hydrochloric acid, not with 1 +1 hydrochloric acid, or more difficult to dissolve. Temperature should not be too high, or hydrochloric acid