题干

化学与材料、生活和环境密切相关.下列有关说法中错误的是(  )

A:食品袋中常放有硅胶和铁粉,都能起到干燥的作用

B:明矾净水时发生了化学及物理变化,能起到净水作用,而没有杀菌、消毒的作用

C:大力实施矿物燃料脱硫脱硝技术,能减少硫、氮氧化物的排放

D:某新型航天服材料主要成分是由碳化硅、陶瓷和碳纤维复合而成,它是一种新型无机非金属材料

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答案(点此获取答案解析)

A

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阅读与回答问题
    Do you feel lonely when your best friend isn't around? Of course, yes. Here's our advice to you—and to all kids who feel lonely sometimes. 
You may feel lonely at break or lunchtime when a best friend isn't around—maybe because he or she moved to a different school or a different class. You want to have new friends, but how do you make them? Maybe it seems everybody else already has his or her friends. But remember, there's always room for more friends.
    Start by looking around your classroom—think about which kids you'd like to play with at break. Look for chances to say hi to them, smile, and be friendly. Offer to share something or express your appreciation (欣赏) to them. Invite someone to play with you or say, “Do you want to sit here?” in the lunchroom. When you're at break, walk over to kids you want to play with, act friendly, and say “Hi, can I play, too?” or just join in. 
     If you have trouble doing this or if you're feeling shy, ask your teacher to help you make new friends. Teachers are usually pretty good at matching up friends. The best way to make friends is to be a friend. Be kind, be friendly, share, say nice things, offer to help ---and pretty soon, you'll have one, or two, or even more new friends.
    You might still miss that special best friend. But when you see each other, you can share something you didn't have before he or she left. You can introduce him or her to your new friends!