问题
选择题
不同物质的溶液的酸碱性不同，根据下表中pH的情况判断，下列说法中正确的是（
| 盐酸 | CuSO4溶液 | NaCl溶液 | 水 | Na2CO3溶液 | NaOH溶液 | |
| pH | ＜7 | ＜7 | =7 | =7 | ＞7 | ＞7 |
A．pH＜7一定是酸的溶液
B．pH＞7一定是酸的溶液
C．pH=7一定是酸的溶液
D．盐的溶液可能显酸性、碱性或中性
答案
答案：D
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不同物质的溶液的酸碱性不同，根据下表中pH的情况判断，下列说法中正确的是（
| 盐酸 | CuSO4溶液 | NaCl溶液 | 水 | Na2CO3溶液 | NaOH溶液 | |
| pH | ＜7 | ＜7 | =7 | =7 | ＞7 | ＞7 |
A．pH＜7一定是酸的溶液
B．pH＞7一定是酸的溶液
C．pH=7一定是酸的溶液
D．盐的溶液可能显酸性、碱性或中性
答案：D
| 完形填空 I finished my last work of the week and could hardly wait to get home, take off my nursing shoes, and relax. As I _1_ my car, I saw one of my _2_ standing by the bus stop. I thought it would only take a couple of extra minutes to give her a ride home, and _3_, it was too cold to be standing outside on the coldest _4_ in January. I didn't know where she lived, but I was _5_ I would be able to find my way back. We _6_ about our work as I drove and _7_ we knew it, we arrived at her house. I started driving back. _8_ looked familiar, but at first that didn't _9_ me. But soon I _10_ something wrong. I recognized nothing. But I told myself to stay _11_. I was _12_ neighborhoods, streets and even streetlights. I no longer knew where I was now. How could I be so stupid! I looked down at my _13_. It was now 2:30 a.m. My gas was slowly running out. I _14_ the car and turned off the engine. In total defeat, I put my head down on the wheel, _15_. Then I raised my head and saw a(n) _16_ down the road in front of me. I turned my headlights on. A car! I drove a little _17_, got out of my car and knocked on the window of that car. An elderly man _18_ rolled his window down. I said that I didn't know how to get back into town. In silence, he started driving. I ran back to my car and drove behind him. Finally I _19_ a familiar street. As I turned to head home, the car disappeared. Then I _20_ my driveway (车道) when the warning light for my gas tank (汽油箱) turned on. Though so many years have passed, I still thank the old man from my deepest heart. | ||||
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