A:向水中加入稀氨水,平衡逆向移动,c(OH—)降低
B:向水中加入少量固体硫酸氢钠,c(H+)增大,Kw不变
C:向水中加入少量NaCl溶液,平衡不移动,c(H+)降低
D:将水加热,Kw增大,c(H+)不变, pH不变
C
Welcome to Class 4, Grade 7. This is our classroom. There are twenty boys and twenty -four girls in the classroom. The teacher's desk is in the front of the classroom. There is a big blackboard on the front wall and a small blackboard on the back wall. There are two maps on the wall. One is a map of China and the other is a map of the world.There are some photos on the wall. There are some flowers by the windows. Our classroom is very beautiful.
①选择调查范围
②设计调查路线和方案
③作好记录
④明确调查目的和对象
下列各句中,没有语病的一项是( )
用下列物质的序号填空:
A.碳酸钙 B.硝酸钾 C.氢氧化钙 D.氯化钠