Yesterday evening, when I went to town with my 1, we met a strange old man. It was raining 2and we had no umbrella. We were trying to get into a taxi when he came up to us. He was carrying a nice 3 and he said he would give it to 4 for only one pound.  He said he had 5 his wallet and he needed taxi fare(费用) to go back home. My mother didn't believe 6 he said at first, and asked him a lot questions. but she finally believed the man and gave him a pound. She was 7 to buy a good umbrella for so little. but the old man didn't get into a taxi. We followed him and found he went into a pub(酒吧) and bought 8a glass of whiskey(威士忌) with a pound. 9he drank it, he put on his hat and took one of the many wet umbrellas there and went off with the new one. Soon after that, he 10 it again.

实验室制取CO₂一般有以下五个步骤：①检查装置气密性②向长颈漏斗中注入盐酸③按要求装配好仪器④收集气体⑤向反应容器中放入大理石．操作顺序正确的是（　　）

A﹣D是初中化学常见的物质，其中A为黑色固体，D为蓝色沉淀，它们之间的相互转化关系如图所示，其中部分生成物和反应条件已省略．

（1）A物质的化学式为：____ ；A物质还可以与____ （写一种）反应生成B物质．

（2）反应④的化学方程式为：____；在①﹣④的反应中属于置换反应类型的有____ （填写序号）．