题干

 室温时,将氢氧化钠溶液与盐酸用滴加方式反应时,溶液的pH随滴入溶液体积变化如图所示.下列有关说法不正确的是(  )

A:该图象表示的是将氢氧化钠溶液滴入盐酸中

B:氢氧化钠溶液和盐酸恰好完全反应时.溶液的pH等于7

C:当滴入溶液的体积为5mL时,所得溶液中的溶质只有NaCl

D:滴入溶液体积为15mL时,再加几滴紫色石蕊试液溶液呈蓝色

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答案(点此获取答案解析)

C

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阅读下文,回答相关问题。

                                                                                         大脑、智商与基因
       ①人类进化到现在的特征和相貌其实不仅仅是因为自身所拥有一些特殊的基因,同时也取决于人类丢失或自我删除了一些可能无用或制约自身发展的基因,而这些基因与大脑的容量和智商都有关系。
       ②人与黑猩猩的亲缘关系最近,但是两者的形状却有较大不同。其中,人类产生意识和决定行为的大脑与黑猩猩的大脑有显著的差异。人的大脑重量约为1300~1500克,而黑猩猩的大脑重量只有约500克,人脑容量大约是黑猩猩大脑容量的3倍。
       ③美国斯坦福大学医学院的吉尔·贝吉拉诺等人进行的一项研究比较了人和黑猩猩及其他哺乳动物的遗传密码,发现了人与灵长类动物在大脑以及其他方面形状差异的奥秘。
       ④研究人员在黑猩猩和其他哺乳动物中发现了510个基因片段,但是这些基因在人类中却不存在。而新发现的这些基因基本上都是调控基因,它们的功能是开启或闭合邻近的大量基因。然后,研究人员对这些人类缺失的基因进行分析,确定了它们是群集在一些特殊的基因周围。这些缺失的基因有什么功能呢?首先,研究人员确定了这些在人类身上缺失的基因可参与类固醇激素的信号调节;其次,还有一些缺失的基因可参与大脑的发育。
       ⑤在这510个黑猩猩拥有但人类缺失的基因中,研究人员发现有一个基因是控制大脑发育的,就像一个闸门或开关,它如果存在,则位于一个抑癌基因GADD45G的旁边。但是,正是由于人类的这种基因缺失,才使得大脑的发育可以不受太多控制,所以大脑发育得更大,大脑的容量也增多,从而产生了更多的神经元,使人类的智能和意识有了飞跃的发展。

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配对阅读: 左栏是五个人物的简介,右栏是七个新款科技产品广告。请将这五个人与他们感兴趣的产品配对。

____George is a boss. He often flies to different cities for business. He always asks others, “Where is the nearest post office?” “Where's the nearest hotel?” etc.

____Terry is a bank clerk. He is single and quite lazy. He doesn't like washing clothes at all, and he hate ironing.

____Dale is a middle school student. He likes listening to music. He dreams to have a pen which can play music while doing homework.

____Alice is a housewife who has two children. She likes to take photos of something her kids are doing, whenever she wants to.

____Kate is a university student. She loves all kinds of toys, especially robots. She hopes to have a robot which can do something for her.

A. Le Pen

Le Pen, with a music player planted inside, plays music while you write on paper and stop when you stop writing.

B. Android Wear

Google is developing a smart watch called Android Wear. The watch uses a touch screen and a voice control. Simply say “OK, Google” to ask whatever you want to know.

C. One Wheel

In the near future you may find a new way to escape traffic: a self-balancing skateboard called One Wheel. It can go as fast as 19 km an hour.

D. Mip

Mip is a playful robot. It stands 19cm tall. You can control it simply with your gesture(手势) or a smart phone. Mip can run, balance and dance on two wheels. It can also bring you a bottle of water.

E. Google Glass

Google Glass is a pair of glasses with a battery(电池) inside with a camera and screen. You can take hands-free photos or videos of anything people are doing.

F. A New Kind of Shirt

Hate washing? You're going to love this kind of shirt made by an American clothing company. This shirt can be worn for 100 straight days without washing. It never needs ironing(烫衣).

G. A Tablet Computer(平板电脑)

A tablet computer is a complete mobile computer, larger than a mobile phone. It has a flat touch screen and you can operate it by touching the screen.