【题目】欲除去下列物质中的杂质,把适用的试剂、操作方法的序号写在相应的横线上。
①加适量盐酸、过滤、蒸发;②加适量水、过滤、蒸发;③加适量水、过滤;④加热(或高温灼烧);⑤加适量盐酸、蒸发。
(1)碳酸钙中含有少量Na2CO3:________。
(2)KCl粉末中含有少量K2CO3:________。
(3)CaO中含少量CaCO3:________。
(4)MnO2中含有少量炭粉:________。
(5)KCl中含有少量MnO2:________。
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【题目】 Parents should encourage teenagers to do social work for their __________ /k'mju:nt/.
A. celebration B. community C. chopstick D. chemistry
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【题目】Sonia Hall喜欢运动,她不仅每天运动,而且常在电视上看比赛。她收集了5个篮球,3个排球,9个足球,6个网球拍,8个乒乓球和球拍。写一段话,介绍一下Sonia Hall所收集的体育用品。
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【题目】—Kitty, how does your brother look like?
—__________.
A. His name is David. B. He is tall and slim
C. He is 13 D. He is a student.
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【题目】 Most Chinese people like red because they think it can __________ them good luck.
A. carry B. bring C. take D. make
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【题目】下表是某实验报告中的一组数据:
实验 序号 | 试剂1 | 试剂2 | 混合前 温度/℃ | 混合后最高或最低温度/℃ |
① | 3.2 mL水 | 3.2 g Na2CO3固体 | 20 | 24.3(t1 ) |
② | 35 mL稀盐酸 | 3.2 g Na2CO3固体 | 20 | 25.1(t2 ) |
③ | 35 mL水 | 2.5 g NaHCO3固体 | 20 | 18.5(t3 ) |
④ | 35 mL稀盐酸 | 2.5 g NaHCO3固体 | 20 | 16.2(t4) |
(1)从实验①、③数据可知:Na2CO3溶于水________热量,NaHCO3溶于水________热量(填“放出”或“吸收”)。
(2)根据t2>t1 可知Na2CO3与稀盐酸反应______热量,根据t4<t3 可知:NaHCO3与稀盐酸反应______热量(填“放出”或“吸收”)。
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【题目】A
Tony and Anna are brother and sister. They are Americans. Tony likes sports very much. He can play football, basketball and volleyball. Anna likes music very much. She can’t play ball games. But they both like playing games on computers.
They like eggs, bread and milk for breakfast. For lunch, Anna likes eating vegetables and fruit, but Tony likes chicken and fish. They both like hamburgers. But they don’t like ice cream or cheese.
【1】 Anna is Tony’s __________ and they are __________.
A. sister; Chinese B. sister; Americans
C. friend; Americans D. brother; Americans
【2】 Tony likes __________ and he can play __________.
A. sports; games B. music; basketball
C. sports; volleyball D. sports; tennis
【3】Tony and Anna both like __________.
A. vegetables B. football
C. playing games D. ice cream
【4】For breakfast, they like __________.
A. eggs, bread and milk B. ice cream or cheese
C. chicken and fish D. vegetables and fruit
【5】 They don’t like __________ or __________.
A. ice cream; vegetables B. ice cream; cheese
C. chicken; fish D. hamburgers; cheese
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