问题 填空题

元素周期表是学习化学的重要工具.下面是元素周期表中1~18号元素原子核外电子排布,我们对它进行研究:

(1)第12号元素属于______元素(填“金属”或“非金属”),它的元素名称是:______;它在化学反应中容易______(填“得”或“失”)电子,所形成的微粒的符号:______.

(2)元素的化学性质与原子结构中的______数关系密切.

答案

(1)根据元素周期表可知,第12号元素名称是镁元素,它属于金属元素,它在化学反应中容易失电子,而带两个单位的正电荷,它的离子符号为Mg2+

(2)原子在相互化合是存在得失电子或形成共用电子对,都与最外层电子数有关,所以元素的化学性质与原子的最外层电子数关系密切.

故答案为:(1)金属;镁;失;Mg2+

(2)最外层电子

阅读理解

What makes humans smarter than other animals? We’ve got a bigger brain, of course. But when it comes to brains, is bigger always better?

Traditionally, scientists have thought that humans’ superior intelligence derived(源于)mostly from the fact that our brains are three times bigger than those of our nearest living relatives, chimpanzees. People even used to believe that because men have slightly larger brains than women that men are smarter.

This, however, is not the truth. Scientists at University College London in the UK have found that brain organization, and not brain size, is the key to the superiority of human intelligence, reported Live Science.

Through millions of years of evolution, our ancestors were constantly pushed to get smarter so that they could meet the demands of new environments. However, holding this growing intelligence in increasingly large brains was not the best choice because bigger brains require more energy to power. “This is when reorganization may come into play, ”said Christophe Soligo, a member of the London research team.

In the study, scientists looked at the brains of 17 species of primates(灵长目动物), including monkeys, apes and humans. They found that in the process of evolution, brains didn’t keep growing as a whole. Certain regions of the brain grew prior to others in response to species’ needs, and in this way they could make the best use of their limited brain space.

For example, when early humans were struggling to survive, the brain region in charge of using tools and finding food grew in size more than other regions. But in modern times, the prefrontal cortex(前额皮质)—the region in charge of social cognition(认知), moral judgments and goal-directed planning—grew more than the rest of the brain.

Think of the brain as a room. If a big room is poorly organized, it doesn’t necessarily store more stuff than a smaller one.

Paul Manger, professor at the University of the Witwatersrand, South Africa, explains this principle using the example of whales. He told Scientific American: “Whales have big brains, absolutely. But if you look at the actual structure of the brain, it’s not very complex. Brain size only matters if the rest of the brain is organized properly. ”

小题1:It has recently been found that humans are smarter than the other animals mainly because   .

A.they are a species of primates

B.they have much larger brains

C.their brain structure is more complex

D.they were constantly pushed to get smarter小题2:According to the article, in recent human evolution,    .

A.the brain kept growing in size to adapt to new environments

B.most regions of the brain didn’t change

C.the prefrontal cortex grew more than the rest of the brain

D.humans’ brains became increasingly simple so that humans could survive小题3:What can we conclude from the article?

A.Gender makes a difference in intelligence.

B.The size of the brain has nothing to do with intelligence.

C.Species whose brain is organized properly tend to be smarter.

D.Larger brains are usually organized better than smaller ones.小题4:The method the writer uses to develop the last paragraph is   .

A.by presenting research data

B.by giving examples

C.by making a comparison

D.by analyzing cause and effect

单项选择题