题干

W、X、Y、Z是原子序数依次增大的短周期主族元素,W是地壳中含量最多的元素,X和Z原子最外层电子数相同,Z的原子半径是同周期主族元素中最小的,Y原子的核电荷数是周期数的4倍。下列说法正确的是(   )

A:氢化物的沸点:X<Z

B:简单离子半径:W>Z>X>Y

C:Y单质着火可用泡沫灭火器灭火

D:X单质可从W的简单氢化物中置换出W单质

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答案(点此获取答案解析)

D

同类题2

阅读下列短文,从下面每小题的A、B、C、D四个选项中选出最佳选项。

    There is always a shadow of shopping in life. You like this, look at that, and then buy a lot of things and go home. Then you calm down and find out that the shopping doesn't make any sense but waste money. How do you avoid the wrong shopping? I'll give you a few tips today!

⑴Buy good quality — and use it

    It's common for people to almost never use the things they love the most. Why? Often, it's because they want to protect the item. They like it so much and don't want it to be ruined. Instead of using their favourites, they buy much cheaper things for "everyday" use. The smarter way is to put your money on something with good quality and good style that you love very much and enjoy it the most. It stops you from wasting money on unnecessary things.

⑵Play the waiting game

    Before you decide to pay for something you like very much at first sight, wait for at least 20 minutes. Then, after clearing your head, think about how and when you'll actually use the product. Instead of simply choosing to have it or not have it, think for a moment and ask yourself whether there is something else even more important you should buy. It reminds you to save money.

⑶Buy only what you need, right now

    Besides, what makes shopping so alluring (欲罢不能的) is your idea that comes with imagining how a product can be used, such as "I will look like a princess in the evening dress at the ball one day." Before paying for a product, ask yourself if you will use it in the very near future. If the answer is no or not likely, pass.

⑷Buy for the right reason

    Research shows that we may think we're hungry when we are actually thirsty, and think we are tired when we are bored in reality. In other words, we know when we need something to satisfy ourselves, but we're not good at realizing what we truly need. It is smart to always ask yourself why you need the product before you pay for it.

同类题4

阅读材料,回答下列问题。

材料一:秦王嬴政统一六国后,采用“皇帝”称号,总览全国一切军争大权。中央政府设丞相、太尉、御史大夫分管行政、军事和监察,最后由皇帝决断。在地方上,建立由中央直接管辖的郡、县二级行政机构,分天下为36郡,郡下设县。郡的长官称郡守,县的长官称县令。各级官员都由朝廷直接程任免。隋唐时期,在中央实行三省六部制。三省是指中书省、门下省、尚书省,尚书省下设六部,分别负责贯彻各种政令,处理日常事务。三省六部间既分工合作,又互相牵制。

——选自《历史七年级》

材料二:公元69年,汉明帝任用杰出的水利家王景治理黄河。王景采取黄河、汴河分治而叉统筹兼顾的方案,使河不侵汴,各安其道。具体方针是“筑堤,理渠,绝水,立门,河、汴分流,复其旧迹”。这次治河使黄河安流将近800年。汉武帝时开凿了漕渠和白渠。漕渠自长安至黄河,长约三百里,既可灌溉田亩,又可通漕运。白渠引泾水入渭水中,可灌溉良田万余顷。

——选自《文物秦汉史》

材料三:从西汉开始,中国的丝绸沿着丝绸古道,运到地中海地区,很快成为那里各个民族、各个社会的普遍追求,丝绸贸易成为古代世界最大宗的贸易。13世纪末以后,中国的丝绸锦缎又成为意大利各地显贵及罗马教廷的时兴服饰。从唐代开始,瓷器在中国对外输出品中逐渐成为大宗货物。在17世纪以前,瓷器在欧洲只是一种新奇的珍玩,到了18世纪初,瓷器开始走入千家万户并成为当时上层社会的收藏品及装饰品。

——选自《中国历史文化》

材料四:在唐朝周边,少数民族建立的地方政权很多,其中有南方的南诏。南诏的生金、丹砂、浪人剑、棉布等土特产传入唐朝,南诏乐也传入唐朝。南诏从汉地吸收不少农业、手工业生产技术。成都工匠在南诏传授纺织技艺,南诏手工业发达起来,与蜀地不相上下。唐文化也大量传入南诏。

南诏遗址出土的有字瓦                   南诏遗址出土的建筑材料方形花砖(左)

                                                      莲花纹瓦当(右)滴水瓦(下)

遗址内这些有字的瓦和陶片,质地青灰色,相当坚硬,瓦上印有文字,这些文字类似汉字。方形花砖和莲花纹瓦当,其形制和纹样都与唐长安城大明宫和兴庆坊出土的砖瓦几无二致。

——选自《文物隋唐史》