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题目(2001年天原杯复赛第27题)由某物质R和Na2SO4组成的固体混合物放入足量水中,充分搅拌,过滤后得到白色沉淀11.65 g,经试验,该白色沉淀不溶于稀硝酸,滤液呈碱性.加入稀盐酸中和滤液,当加入146 g 5%的盐酸时溶液恰好呈中性.求混合物中R的质量.原解由题意知R为Ba(OH)2.设参加反应的Ba(OH)2质量为x,生成NaOH的质量为y.
Title (2001 Tianyuan Cup rematch 27 questions) by a substance R and Na2SO4 solid mixture into a sufficient amount of water, stir, filtered to give a white precipitate 11.65 g, the test, the white precipitate is not soluble in dilute nitric acid, The filtrate was alkaline.Add dilute hydrochloric acid and the filtrate was neutralized when 146 g of 5% hydrochloric acid was added, and the mass of R in the mixture was determined.The original solution was derived from the problem that R is Ba (OH) 2. The mass of reacted Ba (OH) 2 is x and the mass of generated NaOH is y.