溶液对人类的生产、生活都有很重要的意义．下列关于溶液的说法或做法错误的是（ ）
A．夏天喝的汽水不是溶液
B．蛋汤太咸，加水稀释后口味变淡
C．鱼塘中放置喷水泵的作用是增加水中氧气的溶解量
D．凉茶水是均一、稳定的混合物
答案：A
题目分析：A、汽水是一种均一、稳定的混合物，属于溶液，故A说法错误；
B、蛋汤太咸，加水稀释后，汤的浓度小了，变稀了，口味变淡，故B说法正确；
C、鱼塘中放置喷水泵是为了增大水与空气的接触面积，增加水中氧气的溶解量，故C说法正确；
D、凉茶水是均一、稳定的混合物属于溶液，故D说法正确．
故选A．
点评：应熟悉溶液是一种均一稳定的混合物，在不改变条件时，溶液的组成和浓度都不会发生变化，要与悬浊液和乳浊液区分．
Dear Dad, I’m writing to you because it’s not easy to talk about it. I still 1 clearly how my uncle died two years ago. In fact, I seriously want to ask you to stop smoking. I’ve looked up a lot of information about smoking and I found out something 2 . You know that smoking is bad for your 3 and can cause cancer. I’ve learnt that it causes many other 4 too. Do you know that over ten thousand people die from smoking every year in Britain? When mum asks you to smoke 5 , you think she’s angry. Well, it’s true that she doesn’t like the 6 of smoke in the house. When you smoke, it’s also 7 for mum and me. In other words, when we 8 in your smoke, it’s like we’re smoking ourselves. 9 , we can also get disease. Doctors are finding that more and more 10 are falling ill because of the others’ smoking. I know that it’s very 11 to stop smoking, but you must give it up. Please see the doctor and ask him 12 help. We will do anything we can to help you. You must try to 13 your own life. We don’t want to 14 you because you are so important to us. 15 you, who can help me with my maths homework or mend my bike? Please don’t smoke! Your daughter, Meimei
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