下列反应中属于氧化还原反应的是 ( )
A．SO2 + H2O ="==" H2SO3
B．2NaHCO3
Na2CO3 + H2O + CO2 ↑
C．2FeCl2 + Cl2 ="==" 2FeCl3
D．Al(OH)3 + 3HCl ="==" AlCl3 + 3H2O
答案：C
题目分析：凡是有元素化合价升降的反应都是氧化还原反应，C中氯元素的化合价降低，铁元素的化合价升高，所以选项C是氧化还原反应，其余都不是氧化还原反应，答案选C。
点评：氧化还原反应的实质是电子的转移，因此表现在元素的化合价上必然发生变化，据此可以判断反应是不是氧化还原反应。
第四部分 任务型阅读（共10小题；每小题1分，满分10分） 认真阅读下面短文，并根据所读内容在文章后表格中的空格里填入最恰当的单词。 (注意：每空填1个单词。) “BANG! BANG!” Setting off firecrackers(爆竹), which has been the most typical custom on the Spring Festival, is the happiest part of the Festival for most Chinese kids. They light the fuse(导火线) nervously, run away in a hurry, cover their ears with their hands and watch the colorful display with a big smile on their faces. Faced with the beautiful scene, they feel they are the happiest ones in the world as if they had never had a more exciting experience. While setting off firecrackers can bring kids so much fun, these firecrackers can also be dangerous. Therefore, many Chinese big cities including Beijing began to ban them in the 1980s. Such an activity was completely or partially forbidden in big cities because the government took security, noise and pollution factors into consideration. As a replacement, some buy tapes with firecracker sounds to listen to, some break little balloons to get the sound too, while others buy firecracker handicrafts to hang in the living room. This year good news came for teens in Beij ing. The ban on firecrackers was cancelled on September 9, 2008. It will add much fun to the coming Spring Festival in tile capital. Hearing the news, many  kids were wild with joy.According to Chinese custom, lighting firecrackers is a must during the Spring Fesrival. People believe the sound of the firecrackers drives away demons(恶魔) and bad luck for the coming year. Their beautiful colours and sound also bring much excitement during this most important traditional Chinese festival. Since the ban, people complained that the Spring Festival was too quiet and not traditional enough. Children lost the fun and grown-ups lost their childhood memories. Some even worried that if the ban continued, the next generation would only know the custom of lighting firecrackers through books. This would be a great loss for tradition. Everybody knows that we can’t give up eating for the slight risk of choking(因噎废食). So in recent years, many cities have resumed the old custom at the request of local residents. This year Beijing kids will also be able to join in. However, every year there are kids injured by setting off fireworks in a dangerous way. So while enjoying yourself, please bear safety in mind. Don’t light fireworks among crowds, inside a bottle or with a part of your body right over it. No matter how much fun firecrackers are, the most important thing is to keep away from danger. We wish every kid an exciting and safe Spring Festival! Title：Firecrackers back in Beijing on the Spring Festival
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