题干

下列知识整理的内容不完全正确的一组是(  )

A.食品保鲜的办法

B.物质与构成的微粒

真空包装一放置氧化而变质

加入干燥剂CaO一防止受潮腐烂

密封保一繁殖受潮、挥发和变质等

铜由原子直接构成

氧气由氧分子构成

氯化钠由Na+和Cl构成

C.日常物质的鉴别

D.化学与社会、生活

硬水和软水一肥皂水

氦气和二氧化碳气一用澄清石灰水

黄金和黄铜一用稀硫酸

降低水硬度方法:煮沸和蒸馏

铵态氢肥不能与碱性物质混用一导致肥效降低

塑料、合金、合成橡胶一属于有机合成材料

A:A

B:B

C:C

D:D

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答案(点此获取答案解析)

D

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    One night, Steve and Julie are watching a film at home. The film is t____ because it makes Steve bored and Julie c____. Then, Julie hears a noise from the o____. Steve goes out to check and l____ Julie alone in the room. Julie is s____. At this moment, Steve wants to play a joke on Julie. He howls like a wolf(像狼一样叫), which makes Julie cry. What an i____ he is!

    People from different places have different lives. Calvin lives on a small i____ in Scotland. There isn't a school there so his mother t____ him and his three sisters at home. Mawar lives in a v____. It is a seven kilometer walk to a r____ school. Mawar says that she never goes to that school because it is too far away and there are always s____ and rain. Does that mean Mawar studies at home too? Well, no. There is a t____ school near her home. She and 100 other pupils have their lessons there every day.

    Claire is a sixteen-year-old British girl. She lives in s____ England. She doesn't watch TV every day because in her o____, it can be a w____ of time. And she is s____. She only watches the programs that she likes. C____ are her favorite. She thinks people do great things in these shows. She also watches d____. Sometimes, she watches cartoons at the weekend.

    People eat u____ food around the world. For example, people in Japan like eating r____eggs and in China there are many good d____ with snake in them.

    Sally is a chimpanzee and Paula is a little girl. But they have got many s____. They are both very i____ and they've both got four f____ and a t____  on the hand. When they are happy , they both jump up and down and l____ . Why are they so similar? Because they've got almost the same DNA. DNA is the c____ in our bodies that m____ us people, or chimpanzees, or fish, etc. N____ percent of their DNA is the same. There's only a 2% d____.