题目

某化学兴趣小组的同学将一定量的铁与浓硫酸加热，发现铁完全溶解，并产生大量的气体X。该兴趣小组同学欲通过实验探究气体X的成分。 （1） Ⅰ．提出假设①甲同学认为气体X为SO2。②乙同学认为气体X为H2。③丙同学认为气体X为。 （2） Ⅱ．设计实验兴趣小组的同学设计了如图所示实验装置对气体成分进行验证，请按要求填写表格。实验现象实验结论 ①C中酸性高锰酸钾溶液颜色 ②E中粉末，F中晶体证明气体X中含有H2 根据实验现象，可 This is my school. There are many trees and flowers in it. The classroom building is big and tall. There is a big playground in our school. It’s very nice to have it. After 4:30 in the afternoon, many students come to the playground to play football and some students play table tennis in the table tennis room, then they go home.There are 1,000 students in 24 classes in our school. The students all like to study. The teachers in our school are very good. They help the students to study and sometimes play with them. All the students like them.【1】The classroom building is _____.A. small B. old C. big and tall D. big【2】It’s very nice for this school to have _____.A. trees and flowers B. a playgroundC. students D. teachers【3】There are at least (至少) _____ students in one class.A. 45 B. 40 C. 75 D. 60【4】 After class many students often play football _____.A. in their classrooms B. in their homesC. on the playground D. in the classroom building【5】What may (可能) the teachers NOT DO?A. Give the students lessons.B. Play football and table tennis with the students.C. Don’t like some students.D. Help students study.