设计两种不同的实验，证明二氧化碳通入水时，确实发生了化学反应．请分别写出这两个实验过程中的实验现象和结论．
（1）实验一______；
（2）实验二______．
（1）二氧化碳与水反应生成碳酸，碳酸遇紫色石蕊溶液变红色，故可将C02通入水中，再滴入紫色石蕊试液，溶液显红色，说明有酸生成．
（2）二氧化碳与水反应生成碳酸，碳酸中存在能自由移动的氢离子和碳酸根离子，其导电能力比纯水强，故可测试水的导电性，通入C02后的水比纯水的导电能力强，说明确实发生了化学反应．
故答案为：（1）将C02通入水中，再滴入紫色石蕊试液，溶液显红色，说明有酸生成；
（2）测试水的导电性，通入C02后的水比纯水的导电能力强，说明确实发生了化学反应．
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| During my second year of college, I was looking around for a place to live. One Sunday after church, the pastor (牧师) told me to stay in his daughter's room because his daughter was studying abroad for one year. To be 1 , I really didn't want to stay with"the pastor's family". He told me how much the 2 would be-a very low figure that 3 one home-cooked meal a day. I thought about the 4 and decided to move in. At the end of the term I had planned to find 5 living place, since the daughter was to 6 home. To my delight, they 7 that I share a room with their son. I seemed to have been adopted into their 8 -their people became my people. I 9 accepted the offer. As I emptied the daughter's bedroom, I thought it might be 10 to have a little sister to look after. But when I later met my new sister, I 11 that she was more independent than I first 12 . We finally fell in love, 13 , and have looked after each other for many years. There have been times that life turned out more 14 than either of us could have known. But we have al- ways been able to go 15 largely because we knew that we are deeply 16 . It isn't about marriage-lt's about 17 . It's about mothers and fathers, sisters and brothers and special friends who are as 18 as family. It's about anybody who can say, "I'll be 19 - you can count on me. I'll try to look after you and sometimes I will need you to look after me. Is there somebody you can depend on? And are others count ing on you? We travel the path of life best when there is 20 to look after, and when someone is looking after us. | ||||
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