问题
填空题
下列反应中，属于放热反应的是________，属于吸热反应的是________。
①煅烧石灰石（主要成分是CaCO3）制生石灰(CaO)
②燃烧木炭取暖
③炸药爆炸
④酸与碱的中和反应
⑤生石灰与水作用制熟石灰
⑥食物因氧化而变质
答案
②③④⑤⑥ ；①
搜题请搜索小程序“爱下问搜题”
下列反应中，属于放热反应的是________，属于吸热反应的是________。
①煅烧石灰石（主要成分是CaCO3）制生石灰(CaO)
②燃烧木炭取暖
③炸药爆炸
④酸与碱的中和反应
⑤生石灰与水作用制熟石灰
⑥食物因氧化而变质
②③④⑤⑥ ；①
We don’t have special skills but all of us can be special people. Why? Because we can volunteer. Mary, a Canadian girl, was sad because she had a heart problem. Her classmates had always been trying to her up. However, they couldn’t because she was so that she needed lots of money to have an operation (手术）. Her parents to get help from the public. A TV station soon a call-in center for Mary. Many people called and offered to help Mary . At the same time, Mary’s classmates donated (捐赠）money, and some of them even handed out notices Mary’s story at a local supermarket. All above helped Mary a lot. Mary and her parents really everyone’s hard work. There are lots of opportunities (机会) for us to volunteer. The Asian Games in Guangdong, for example, need volunteers. And volunteers are also in local hospitals, old people’s homes, and so on. We can also help homeless people and people, and volunteer to clean up parks. Volunteering is not only a great way to help people, but also a great way to make new friends, to learn new skills, and to have fun.
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