题目

下列各组物质在水溶液中能大量共存的是（ ） A．氢氧化钠和硝酸铵 B．氯化钡和硫酸钠 C．硫酸铜和氯化钠   D．氯化钡和硝酸银 答案：【考点】9R：离子或物质的共存问题． 【分析】根据复分解反应发生的条件可知，若物质之间相互交换成分不能生成水、气体、沉淀，则物质就能大量共存． 【解答】解：A、氢氧化钠与硝酸铵反应生成氨气、水，在水中不能大量共存，故A错误； B、氯化钡与硫酸钠反应生成硫酸钡白色沉淀，在水中不I have a picture of my school. There is a new building in the middle of the picture. There are many flowers and trees near the building. There’re twelve classrooms in it. There’re twenty-four desks for the students and one desk for the teacher in every classroom. Beside the building, there is a big playground. There are some boys and girls on it. They’re playing happily.There are some houses next to the building. They are our library and reading rooms. How many windows are there in every reading room? Four. So it’s bright. Now some students are reading.We all like our school very much.根据短文内容，判断正T和误F。 F T T F F( )（1） I have a picture of a new classroom.( )（2） There is a new building in the school.( )（3） There are twenty-five desks in every classroom.( )（4） There aren’t any flowers or trees near the new building.( )（5） There’re four windows in the building.