题干

从原子序数11依次增加到17,下列所述递变关系中,错误的是(   )

A:电子层数逐渐增多

B:原子半径逐渐减小

C:最高正化合价数值逐渐增大

D:从硅到氯,最低负化合价从﹣4到﹣1

上一题 下一题 0.0难度 选择题 更新时间:2019-06-08 08:16:47

答案(点此获取答案解析)

A

同类题3

根据短文内容,完成下列任务。

    China has its first Nobel Prize in Science. And the winner, 84-year-old Chinese scientist Tu Youyou, also became the first Chinese woman to win the Nobel Prize. She won the 2015 Nobel Prize in Physiology or Medicine with William C. Campbell, an Irish-born researcher, and Satoshi Omura of Japan. The three winners will share the prize of 8 million Swedish crowns ($920,000).

    Half of the Prize was given to William C. Campbell and Satoshi Omura for their new treatment against illness caused by roundworm parasites (寄生虫). Tu Youyou won the other half of the Prize for developing a medicine, Artemisinin(青蒿素), which can help people fight malaria(疟疾). More than 240 million people in Africa have benefited from the treatment, according to the WHO (World Health Organization), and more than 1.5 million lives have been saved since 2000, thanks to the medicine.

    Tu Youyou started her research in 1969 when she was chosen as the director of a government project to find anti-malaria medicines. She and her workmates studied ancient Chinese medicine books and many different traditional treatments. They did nearly 200 experiments before they finally succeeded in getting the material Qinghaosu, later known as Artemisinin, in the 1970s. This medicine became the standard treatment for malaria in the WHO's list of important medicines.

    Premier Li Keqiang congratulated Tu for winning the Prize. He said, "Tu's winning the prize shows China's progress in scientific and technological field, and marks a great contribution of Traditional Chinese Medicine (TCM) to human health."

    Although it's a late honor for Tu and the world's recognition of Traditional Chinese Medicine, Tu's winning the first Nobel Prize in Physiology or Medicine makes Chinese scientists encouraged and confident to achieve more success in the future.

同类题5

阅读下面的文字,完成下列小题。

雕花象牙扇

钱凯

    华灯初上,一辆辆小轿车络绎不绝地驶进古色古香的大院,按序停在绿荫丛中的会议厅前。

    在医学界闻名遐迩的外科专家慕容教授的车来得比较晚,悄悄地停在一侧。司机拉开了车门,后坐上的慕容教授以外科专家习惯,在车内顶灯柔和的光环下又审视了一下请柬的文字,方才款款下车。整个院子笼罩在光辉中,仿若白昼。她抬起头来,幽深的夜空高悬着一轮明月,她失神地凝望着明月,不知在想什么。司机轻轻地提醒着她,她才回过神来,用手抚了抚满头银丝,姗姗步入大厅。

    大厅里飘逸着音乐,那是很好听的《花好月圆》,江南丝竹的味儿,又揉进了电子音乐的伴奏,不高不低,徐缓有致,声声入耳,象是二三开的碧螺春,绵甜、幽香,沁人心脾。她在服务小姐引导下就了座,旁座坐着一位老翁,朝着她的方向看了看,她朝他颔首一笑,算是打了招呼。这位老翁虽然不熟,却也见过几次,大抵都在类似的场合。她只知道他是省内曲艺界硕果仅存的泰斗,一部《三国演义》说了他家祖孙四代,甚是精彩。

    全国各界名人共聚一堂的中秋联欢会一年一度,她被邀的原因大概有很多,然而欣然赴会却是近几年的事情。抓了几十年的手术刀,近几年终于觉得自己太累了;况且,终年独自在家面对孤灯,她也确实是有点厌了。

    节目都是精选的,很像她平素喜欢的小菜,清淡、雅致,却别具—格 正欣赏着,有人来到她席前,递上一个狭长的小纸包,说是刚从海峡彼岸探亲归来,受人之托带来的。她忙道谢、让座,身边那位泰斗刚好上台说书去了,旁边的座位空着。可他不坐。

    他似乎有点误会,也有些激动,“不,该谢的是令亲!我偶感小恙,去了日月潭附近的那座有名的医院,不料,端木院长闻知,竟然亲自为我诊治,且分文不收,说是万里之外见乡亲,岂可言阿堵?!我委实过意不去……”

    听了“端木”二字,她的心骤然紧缩。

    纸包长可七八寸,横头不到一寸见方。她紧紧捏着,欲拆开却又迟疑,心口只是怦怦地跳。40多年前圣约翰大学银杏树下风雨一别,这可恨的书痴竟然还记着我,莫非还是厚厚一叠痴话。想起那些默诵了近半个世纪的痴话,她顿觉面红耳热。她想提前退场,回到卧室,静静地享用这等了太久的音讯。

    不知怎的,她的手却拆开了纸包。是只紫色的天鹅绒小盒。打开小盒,她眼一亮,盒里静静地卧着一柄雕花象牙折扇,正面看反面瞧,一片片扇骨细瞅,竟无一字。她恍然若失,天涯海角地托人送来,竟无片言只字!这木头!

    小姐送来凉毛巾,她在额前拭过,忽觉那精美的雕花、刀法似曾相识。同窗数载,他为了练眼、练手指,一味苦心孤诣。她以为读懂了这“无字书”,于是将折扇合起,缓缓向外走去。

    一阵掌声将她惊住,老翁的《三国演义》博得了满堂彩。她猛然记起老翁最后收篇的警句:……分久必合。

(有改动)