问题 选择题

某探究小组的同学取等质量的A、B金属,分别投入溶质质量分数相同的足量的盐酸中,生成氢气的质量(m)与时间(t)的关系如图(已知A、B元素在生成物中的化合价相同,均为+2价),以下叙述正确的是(    )

A、金属A、B的活泼性:A﹤B

B、到时间t2时,金属均有剩余

C、两种金属原子的相对原子质量A﹤B

D、到时间t1时,产生氢气的质量A﹤B

答案

A、C、D

题目分析:A、金属的活动性越强,反应的速率越快,反应结束所用的时间就越短,从图中可以看出B所用的时间更短,说明金属A、B的活泼性:A﹤B,正确,B、到时间t2时,若金属均有剩余,表示酸全部反应完,而盐酸的溶质质量分数相同、质量也相等,则产生的氢气应该相等,而从图中看出,到时间t2时,A产生的氢气质量比B大,错误,C、因为A、B元素在生成物中的化合价相同,均为+2价,所以可以写出金属与酸反应的通式:R+2HCl=RCl2+H2↑,根据金属与氢气的质量关系可知,当金属质量相等时,产生的氢气质量与金属的相对原子质量成反比,由于最终产生氢气的质量A>B,所以两种金属原子的相对原子质量A﹤B,正确,D、直接由图可知:到时间t1时,产生氢气的质量A﹤B,正确,故选A、C、D

阅读理解

Shopping is not as simple as you think! There are all sorts of tricks at play each time we reach out for that particular brand of product on the shelf.

Coloring, for example, varies according to what the producers are trying to sell. Health foods are packages in greens, yellows or browns because we think of these as healthy colors. Ice cream packets are often blue and expensive foods, like chocolates, are gold and silver.

When some kind of pain killer was brought out recently, researchers found that the colors turned the customers off because they made the product look weak and ineffective. Eventually, it came on the market in a dark blue and white package because we think of it as safe, and white as calm.

The size of a product can attract a shopper. But quite often a bottle doesn’t contain as much as it appears to.

It is believed that the better-known companies spend, on average, 70 percent of the total cost of the product itself on packaging.

The most successful producers know that it’s not enough to have a good product. The founder of Pears soap, who for 25 years has used pretty little girls to promote their goods, came to the conclusion: “Any fool can make soap, but it takes a genius to sell it.”

小题1:Which of the following may trick a shopper into buying a product according to the text?

A.The cost of its package.

B.The price of the product.

C.The color of its package.

D.The brand name of the product.小题2:The underlined part in paragraph 3 means that the colors ________.

A.attracted the customers strongly

B.had weak effect on the customers

C.tricked the customers into shopping

D.caused the customers to lose interest小题3:Which of the following would be the best title for this text?

A.Choice of Good Products

B.Disadvantages of Products

C.Effect of Packaging on Shopping

D.Brand Names and Shopping Tricks

单项选择题