按要求将其化学符号填写在下列空格中．
（1）含氧质量分数最大的氧化物______（2）汽水中含有的一种酸______．
（1）含氧质量分数最大的氧化物是过氧化氢，H2O2中氧元素的质量分数比H2O中的高，所以含氧质量分数最高的氧化物应是H2O2．
（2）汽水中含有的一种酸是碳酸，其化学式为：H2CO3．
故答案为：（1）H2O2；（2）H2CO3．
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| Many young people today care about the way they __1__ . They often buy “designer” clothes __2__ they think they look cool. Then the__3__ well-known companies make clothes which look the same. But they don’t sell __4__ well because they don’t have the __5__ . People __6__ think designer clothes are better made. For example, many people think the right running shoes will make you run faster or play better. Of course, this is not always 7 .It’s the 8 – not the trainers – that improves your speed or your score. 9 that’s not the point. People believe that it’s true … and then 10 the shoes. The big companies only want to make a lot of money. | ||||
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