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问题 选择题

下列有关实验的说法正确的是（　　）

A．定容时仰视容量瓶刻度线会使溶液的浓度偏高

B．可用碱式滴定管量取13.50mL的高锰酸钾溶液

C．过滤时，可用玻璃棒搅拌漏斗中的液体以加快过滤速率

D．从草木灰中提取K2CO3时，将滤液蒸发至仅剩少量液体时即停止加热

答案

A．定容时仰视容量瓶刻度线，溶液的体积偏大，根据C=

n
V
可知所配制溶液浓度偏小，故A错误；

B．高锰酸钾溶液能氧化碱式滴定管中的橡皮管，所以用酸式滴定管量取13.50mL的高锰酸钾溶液，故B错误；

C．过滤时，不能用玻璃棒搅拌漏斗中的液体，防止损坏滤纸，故C错误；

D．在蒸发液体时，一般用蒸发皿，并用玻璃棒搅拌，当加热到出现较多量固体时停止加热，利用余热蒸干，故D正确；

故选：D；

单项选择题 案例分析题

患者，男，45岁，咳嗽伴阵发性心动过速、皮肤潮红3个月，胸片示左侧肺门一圆形巨大阴影，直径5cm。

支气管镜活检镜下如图所示：肿瘤细胞弥漫或成片聚集，细胞体积小，胞浆少，核深染，易见核分裂象。该患者最可能的诊断是（）

A.肺鳞状细胞癌

B.肺腺癌

C.肺小细胞癌

D.肺瘢痕癌

E.肺大细胞癌
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填空题

Tidiness


Tidiness means keeping things out of sight and yet available when wanted. It implies that there is a (1) for everything and that each thing used finds its way (2) to its place by a continuos process, not by a spasmodic (3) . The process depends, however, upon the drawer, cupboard and storage (4) being provided, for lack of which one things may literally have (5) place to go. Like the perambulator and trolley, the luggage and the golfclubs (6) be homeless. The same may be true of the deck-chairs (7) the bulkier plastic toys. As there is no place for them, it is no (8) telling people to put them away. The architect who thus economises on (9) space is apt to claim that a good-sized sitting-room is (10) result. What advantage is there in that, however, (11) half the living-room has to be used for storage The aesthetic (12) depends, in turn, upon storage space. (13) it may be true that no house ever had cupboards enough, (14) are some houses which have practically no cupboards (15) all. In these our choice must lie between chronic (16) and ruthless destruction. That is not to say, however, (17) cupboard space will itself create tidiness. Some people (18) happier, it would seem, in chaos. There is the question, furthermore, (19) the cupboards themselves are tidy. That (20) has been swept out of sight is no proof, in itself, that everything can be found.
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