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注意:1.每处错误及其修改均仅限一词;2.只允许修改5处,多者(从第6处起)不计分,仅涉及修改和添词,不涉及删除。Michael Jackson had been working in music since he was five, which made him very experience in the field. But that inspires me most is his intelligent and honest character. In addition his excellence in music, he loved people with all of his heart. He once says, If you enter this world, knowing you are loved and you leave this world knowing the same, everything that happens in between can be dealt with. He lived by these word and lived his lⅠ.制备水杨酸对正辛基苯基酯()的过程如下:步骤一:将水杨酸晶体投入到三颈烧瓶中,再加入适量的氯苯作溶剂并充分搅拌使晶体完全溶解,最后加入少量的无水三氯化铝。步骤二:按下图所示装置装配好仪器,水浴加热控制温度在20~40℃之间,在搅拌下滴加SOCl2,反应制得水杨酰氯。该反应方程式为:(水杨酸)+SOCl2→(水杨酰氯)+HCl↑+SO2↑ 步骤三:将三颈烧瓶中混合液升温至80℃,再加入对正辛苯酚[],温度控制在100℃左右,不断搅拌。步骤四:过滤、蒸馏、减压过滤;酒精洗涤、干燥即得产品。(1)实验时,冷凝管中的冷却水进口为 _______(选填“a”或“b”);(2)步骤一中加入无水三氯化铝的作用是 ___________________________。(3)步骤三中发生反应的化学方程式为 _____________________________。Ⅱ.PCl3可用于半导体生产的外延、扩散工序。有关物质的部分性质如下:熔点/℃沸点/℃密度/g·mL-1其他白磷44.1280.51.822P(过量)+3Cl22PCl3;2P+5Cl2(过量) 2PCl5PCl3-11275.51.574遇水生成H3PO3和HCl,遇O2生成POCl3POCl32105.31.675遇水生成H3PO4和HCl,能溶于PCl3已知下图是实验室制备PCl3的装置(部分仪器已省略),则:(1)实室制备Cl2的离子反应方程式为:________________。(2)碱石灰的作用除了防止空气中的O2和水蒸气进入并与产品发生反应外还有:_________。(3)向仪器甲中通入干燥Cl2之前,应先通入一段时间的干燥CO2,其目的是_____________。(4)测定产品中PCl3纯度的方法如下:迅速称取m g产品,水解完全后配成500mL溶液,取出25.00mL加入过量的c1 mol/L V1 mL 碘溶液,充分反应后再用c2 mol/L Na2S2O3溶液滴定过量的碘,终点时消耗V2 mL Na2S2O3溶液。已知:H3PO3+H2O+I2==H3PO4+2HI;I2+2Na2S2O3==2NaI+Na2S4O6;假设测定过程中没有其他反应,则根据上述数据,求出该产品中PCl3的质量分数为 ___________________(用含字母的代数式表示、可不化简)。
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