题目

It snowed again.My seventh Christmas was round the corner.I dreamed of getting the present from Father Christmas until my elder sister dropped the bomb.“There is no Father Christmas.”I ran to my grandmother’s house, for she always told the________. Grandmother was at home. I told her everything.“No Father Christmas?”she was a little _____.“Don’t belive it.Put on your coat,and let’s go.” “Go?Where，Grandma?” I asked. “Kerby’s Store.” As we walked through its doors. Grandma handed me the dollars and said.“Take the ____and buy something for someone who needs it.I’索氏制碱又称氨碱法，其主要生产流程如左下图:(1)粗盐中常含Ca2+、Mg2+、SO42-等杂质离子，可依次加入NaOH、____、____、盐酸试剂来进行提纯。(2)用化学方程式表示沉淀池中发生的反应为________________________________。(3)氨碱法制得的纯碱样品中可能会含有MaCl杂质。现用量气法测定纯碱样品的纯度，(如右上图)如何检查该装置的气密性_________________________________，称取m克样品装入Y型管左侧，量气管中液体应为______________(填字母)。A.水 B.饱和食盐水 C.饱和碳酸钠溶液 D.饱和碳酸氢钠溶液(4)若最后测得产生CO2气体的体积为VL(标况下)，则样品中纯碱的纯度为_________。若最后读数时，发现水准管液面高于量气管(其他操作都正确)，则计算所得纯碱样品的纯度值_____(填“偏大”，“偏小”或“无影响”)。