问题
选择题
下列日常生活中的物质，属于纯净物的是（ ）
A．酱油
B．食盐水
C．食醋
D．蔗糖
答案
由多种物质组成的物质，属于混合物；由一种物质组成的物质，属于纯净物．
A、酱油中含有水、氯化钠等物质，属于混合物；
B、食盐水中含有水和氯化钠，属于混合物；
C、食醋中含有水、醋酸等，属于混合物；
D、蔗糖是由一种物质组成的，属于纯净物．
故选D．
搜题请搜索小程序“爱下问搜题”
下列日常生活中的物质，属于纯净物的是（ ）
A．酱油
B．食盐水
C．食醋
D．蔗糖
由多种物质组成的物质，属于混合物；由一种物质组成的物质，属于纯净物．
A、酱油中含有水、氯化钠等物质，属于混合物；
B、食盐水中含有水和氯化钠，属于混合物；
C、食醋中含有水、醋酸等，属于混合物；
D、蔗糖是由一种物质组成的，属于纯净物．
故选D．
It was 3:43. Thunder was crashing and the rain was pouring. Suddenly my father rushed into my room. “Adam! Adam! Get up! We’re flooding!” he shouted and shook me by the shoulders. That woke up! I ran downstairs to the basement. It was like a swimming pool. My mother and I immediately started to pick up things and take them upstairs. I had no on, so my feet were quite freezing. Things got worse every minute. Within the next hour, we had moved everything that we could to the first floor. The computer, big-screen television and heavy boxes with our most valuable things were taken to safety. , our piano, sofa, washing machine and water heater were all still down there—being . There was nothing we could do. That was the hardest part. Knowing that your home is being destroyed is bad enough, but that you can’t do anything to stop it feels even worse. Water had come in our front door. Rescue were floating in our streets. Mother told me to pack an overnight bag of clothes and valuables and get ready to leave. When it was safe to walk outside, all the people in the neighborhood at the street corner. People became friends, and friends became like family. People each other. We learned later that the National Weather Service had declared the storm a flash flood. I really have something from this flood. I’ve learned what destruction is. I have learned what means. I know in the future, when I watch people’ s lives affected by natural disasters, I can understand them. I will show great pity on them and I will do what I can to help them. 小题1:
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