Minions(小黄人) are some small robots in a movie. They are yellow, and they always wear blue trousers. Some have one eye and some have two eyes. Their arms and legs are short, so they look very funny. Bananas are their f  6   food. Minions are small, but they are very smart. ⑵Minions work hard and they have different jobs. Some work as policemen. Some work as tennis players and some work as teachers. Many people like these cute yellow robots. Let's meet three of them.

请按要求完成下列各题

纳米碳酸钙应用非常广泛．实验室中利用下图所示装置（部分夹持装置已略去），向饱和CaCl₂溶液中通入NH₃和CO₂可制得纳米碳酸钙．

供选择的药品：

①石灰石

②氯化铵 

③氢氧化钙 

④饱和氯化钙溶液 

⑤浓硫酸         

⑥6mol•L^﹣1盐酸⑦饱和食盐水⑧饱和NaHCO₃溶液

（1）装置A中，仪器a的名称是____ ，仪器b中发生反应的离子方程式为____ 装置D的试管中发生反应的化学方程式为____ 装置B中盛放的溶液是____ （填药品序号）．

（2）设计一个简单的实验方案，判断所得碳酸钙颗粒是否为纳米级____ （简述实验的步骤、现象和结论）

（3）通入适量气体后，C装置中物质恰好完全反应，过滤，所得滤液显____ （填“酸”、“碱”、“中”之一）性，原因是　____ （用离子方程式表示）．

（4）上述装置存在一处缺陷，该缺陷为____ 

若$\sqrt{x-1}$+（y+2）²=0，则（x+y）²⁰¹⁵等于（　　）

粗盐提纯中几次用到玻璃棒，每次使用的作用各是什么？