A:分解的气体产物中有SO3、SO2,应该先检验SO3
B:装置b中的试剂为Ba(NO3)2溶液,反应后有白色沉淀生成
C:装置c中的试剂为酸性KMnO4溶液,作用是除去混合气体中的SO2
D:装置d之后需要增加尾气处理装置
根据短文理解,选择正确答案。
We are all learning English, but how can we learn English well? A student can know a lot about English, but maybe(可能)he can't speak English.
If you want to know how to swim, you must get into the river. And if you want to be a football player, you must play football. So, you see. You can learn English only by using it. You must listen to your teacher in class. You must read your lessons every day. You must speak English to your classmates and also you must write something sometimes. Then one day, you may find your English very good.
读某地等高线地形图,攀岩是目前一种时尚的运动方式,图中比较适合这一运动的地点是( )
如果此方案正确,那么:
圆柱体的高越长,它的体积越大.
草原上,一只老鼠发现老鹰在上空盘旋,迅速钻进附近的巢穴内.老鼠的这种行为体现了生物( )