问题 填空题

根据题意填写下列空格

(1)烫发用的定型剂主要成分是溴酸钠(NaBrO3),对皮肤有刺激作用,使用不当会引起皮炎.溴酸钠中溴元素的化合价为       

(2)某微粒结构示意图为,用化学符号表示为                  

(3)新鲜的蔬菜水果中含有的营养素主要是               和水.

(4)用洗洁精洗去餐具上的油污属于                    现象.

(5)每年的6月26日是世界禁毒日,今年的主题是“珍惜生命,远离毒品,预防艾滋病”,下列几种物质中①海洛因 ②甲醛 ③摇头丸 ④黄曲霉毒素⑤冰毒,属于毒品的是                (填序号)

(6)现有30℃的不饱和KNO3溶液,与该溶液有关的量有:①水的质量;②溶液中溶质KNO3的质量;③KNO3的质量分数;④30℃时KNO3的溶解度;⑤溶液的质量.用序号填空:

Ⅰ.在该不饱和溶液中加少量硝酸钾至饱和,不变的量有              

Ⅱ.将该不饱和溶液恒温蒸发至饱和,不变的量有              

答案

(1)+5.(2)Al3+,(3维生素,(4)乳化作用,(5)①③⑤,(6)I、①④,II、②④.

题目分析:(1)钠元素的化合价是+1,氧元素的化合价是﹣2,设溴的化合价是x,(+1)+x+(﹣2)×3=0,x=+5,(2)根据圆圈内的数字是13,说明有13个质子,可以知道是铝元素,核外的两个电子层上的数字之和是10,说明有10个电子,质子数大于核外电子数,是阳离子,故答案为:Al3+,(3)蔬菜水果中主要的成分是水,富含大量的维生素;(4)洗洁精在去除油污时,使油污分散成无数细小的液滴,而不聚成大的油珠,细小的液滴能随着水流走,故答案为:乳化作用,(5)毒品是指鸦片、海洛因、甲基苯丙胺(冰毒)、吗啡、大麻、可卡因以及国家规定管制的其他能够使人形成瘾癖的麻醉药品和精神药品,故答案为:①③⑤,(6)I、加入硝酸钾后增加了溶质的质量,而溶剂的质量不变,溶液的质量就改变了,溶质的质量分数就增大了,温度不变,溶解度就不变,故答案为:①④,II、恒温蒸发后,溶剂的质量减少了,溶液的质量就不变,溶质的质量也不变,溶剂少了,溶液也就少了,质量分数就增大了,温度不变,溶解度就不发生改变,故答案为:②④.

单项选择题

Pretty in pink: adult women do not remember being so obsessed with the colour, yet it is pervasive in our young girls’ lives. It is not that pink is intrinsically bad, but it is such a tiny slice of the rainbow and, though it may celebrate girlhood in one way, it also repeatedly and firmly fuses girls’ identity to appearance. Then it presents that connection, even among two-year-olds, between girls as not only innocent but as evidence of innocence. Looking around, l despaired at the singular lack of imagination about girls’ lives and interests.

Girls’ attraction to pink may seem unavoidable, somehow encoded in their DNA, but according to Jo Paoletti, an associate professor of American Studies, it is not. Children were not colour-coded at all until the early 20th century: in the era before domestic washing machines all babies wore white as a practical matter, since the only way of getting clothes clean was to boil them. What’s more, both boys and girls wore what were thought of as gender-neutral dresses. When nursery colours were introduced, pink was actually considered the more masculine colour, a pastel version of red, which was associated with strength. Blue, with its intimations of the Virgin Mary, constancy and faithfulness, symbolised femininity. It was not until the mid-1980s, when amplifying age and sex differences became a dominant children’s marketing strategy, that pink fully Came into its own, when it began to seem inherently attractive to girls, part of what defined them as female, at least for the first few critical years.

I had not realised how profoundly marketing trends dictated our perception of what is natural to kins, including our core beliefs about their psychological development. Take the toddler. I assumed that phase was something experts developed after years of research into children’s behaviour: wrong. Turns out, according to Daniel Cook, a historian of childhood consumerism, it was popularised as a marketing trick by clothing manufacturers in the 1930s.

Trade publications counselled department stores that, in order to increase sales, they should create a "third stepping stone" between infant wear and older kids’ clothes. It was only after "toddler" became a common shoppers’ term that it evolved into a broadly accepted developmental stage. Splitting kids, or adults, into ever- tinier categories has proved a sure-fire way to boost profits. And one of the easiest ways to segment a market is to magnify gender differences—or invent them where they did not previously exist.

The author suggests that our perception of children’s psychological development was much influenced by()

A. the marketing of products for children

B. the observation of children’s nature

C. researches into children’s behavior

D. studies of childhood consumption

选择题