题目： 下列有关实验基本操作和实验现象的描述正确的是（ ）A．用托盘天平称取25.20 g氯化钠B．配制一定浓度的氢氧化钠溶液时，将氢氧化钠固体放在纸片上称量C．用玻璃棒蘸取溶液滴到湿润的pH试纸上,测其pHD．把锌粒放入盛有盐酸的试管中，加入几滴氯化铜溶液，气泡放出速率加快 答案： 答案：D
题型：单项选择题 “It is declared that this shipment does not contain any wood packing materials.”与这句话意思接近的是( )。A．We declare that no wood packing material was used in this shipment.B．No declaration was made whether wood packing materials had been used or not.C．If you don't make any declaration, we will not use any wood packing material.D．We will not use any wood packing material since you have provided us a declaration of no-wood packing material. 查看答案
