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【简答题】
(8分)旺旺雪饼的包装袋内,放有一袋白色固体,上面写着“干燥剂、主要成分为生石灰”。同学们对在空气中放置一段时间的干燥剂进行了探究,根据生石灰的性质变化,设计了下列实验。 【实验操作1】下面是同学设计的探究白色固体组成的实验方案,请你和他一起完成实验报告。 实验操作 实验现象 实验结论 A.将样品研碎放入水中,充分搅拌,静置。 底部有大量白色不溶物出现 白色固体中含有碳酸钙 B.取上层清液,滴加无色酚酞试液。 溶液变为 白色固体中含有氢氧化钙 同学们讨论,认为同个结论都不准确,A是因为 , B是因为(用方程式表示) 。 【实验操作2】小宇同学新设计的探究白色固体组成的实验方案,请你和他一起完成实验报告。 实验操作 实验现象 实验结论 1.取样品放入的试管中,用温度计测量水温先后的情况 温度升高 ____ 2.取样品放入研钵,与硝酸铵一起碾磨 白色固体中含有氢氧化钙 3.取样滴加稀盐酸 有气泡产生 ____ 【拓展与应用】 由小宇实验2(样品与硝酸铵一起碾磨)知道施用铵态氮肥时应注意____。
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【单选题】He was banned __________ for six months because of drunk driving. [      ]
A.
to drink
B.
to driving
C.
driving
D.
from driving
【单选题】以下食物中含锌量最高的是( )。
A.
蛋类
B.
牛肉及制品
C.
豆类及谷类
D.
牡蛎
【单选题】听力原文:W: I have to go to the other side of the town, but it's the rush hour now. M: Driving is not the idea] way. I always take the subway at this time of the day. Q: According to the man, what is the ...
A.
Driving a car.
B.
Taking a taxi.
C.
Going by train.
D.
Taking the subway.
【单选题】听力原文:W: I have to go to the other side of the town, but it's the rush hour now. M: Driving is not the ideal way. I always take the subway at this time of the day. Q: According to the man, what is the ...
A.
Driving a car.
B.
Taking a taxi.
C.
Taking a train.
D.
Going by subway.
【简答题】以下食物中含锌量最高的是
【简答题】After an hour’s train ride and half an hour’s walk, we ually arrived at our _______.
【简答题】外资股是指股份公司向外国投资者发行的股票,不包括向我国、、地区发行的股票。( ) A.正确 B.错误
【单选题】听力原文:W: I have to go to the other side of the town, but it's the rush hour now. M: Driving is not the ideal way. I always take the subway at this time of the day. Q: According to the man, what is the ...
A.
Driving a car.
B.
Taking a taxi.
C.
Going by train.
D.
Taking the subway.
【单选题】Hundreds of Swedish workers are trialing a six—hour working day in the hopes that it will_____ sick leave and save the country money.
A.
cut down
B.
turn down
C.
pull down
D.
cast down
【单选题】以下食物中含锌量最高的是( )
A.
蛋类
B.
大豆及制品
C.
牛肉及制品
D.
牡蛎 等贝壳类
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