【提出问题】这瓶溶液是什么溶液？

【获得信息】实验中用到含有钠元素的物质是氯化钠、氢氧化钠、碳酸钠

【提出猜想】这瓶溶液原来是：

猜想一：氯化钠溶液；   猜想二：氢氧化钠溶液；   猜想三：碳酸钠溶液．

【实验推断】

①甲取样滴加无色酚酞试液，溶液呈红色，得出结论：该溶液不可能是____溶液，理由是____．

②乙另取样滴加稀盐酸有____产生，乙得出结论：该溶液原来是碳酸钠溶液．

③丙认为乙的结论不完全正确，理由是____．小组同学讨论后一致认为还需要进行如下实验：

【继续探究】④另取样加入过量的氯化钙溶液，观察到有____产生，设计这一步骤的目的是；静置后，取上层清液，滴入酚酞试液，溶液呈红色．

【得出结论】⑤这瓶溶液原来是____

【拓展迁移】⑥氢氧化钠溶液与盐酸发生中和反应，恰好完全反应的微观过程如图2所示，反应的实质表达式为：H⁺+OH^﹣=H₂O，则反应后溶液中存在的阴、阳离子是____（填离子符号）；请写出【继续探究】实验中加氯化钙溶液反应的实质表达式：____（仿照上例，用离子符号表示）

黄石市是一座矿冶名城，某中学课外活动小组用天平和量筒測一块矿石样品的密度，请根据题意，完成下列填空

____ you read an encyclopedia，you____ more information about dinosaurs．

阅读理解

    Many other people and I in Britain love charity shops because we can find them on every street．The charity shops sell all kinds of things and they are very cheap．

    The first charity shop was opened by Oxfam in 1947．Now there are over 7,000 charity shops in the UK．My favorite charity shop in my hometown is the Cross Shop．There I always find children’s books，all 10 to 20 pence each．They are really cheap．

    Most of the shop workers in charity shops are volunteers，    each shop has a manager and he gets some money．Every morning you see bags of things outside the shops．Some people bring and put them there without waiting for thanks．In fact，over90％of the things in charity shops are from kind people．

    All the money the shops get goes to charity work．Charity shops raise more than 110 million pounds every year．The money is for sick and poor children。homeless and disabled people，and many others．In a charity shop you can get cheap but nice things．You might even feel special while shopping．

    If possible，let’s do something for charity together．

根据短文内容，完成下列各题。