问题 实验题

某化学兴趣小组同学为了研究影响分子运动速率的因素,如图所示,玻璃管左、右两端分别放有脱脂棉,注射器中分别装有浓盐酸和浓氨水.浓氨水挥发出来的氨气(NH3)和浓盐酸挥发出来的氯化氢(HCl)能发生如下反应,NH3+HCl=NH4Cl.两个注射器同时向脱脂棉靠近里边的部位注入等体积的液体,过一会,先在A处产生大量白烟,然后白烟逐渐充满整个试管.根据现象回答问题:

(1)生成物NH4Cl常温下的状态是                    (填“固体”、“液体”或“气体”);

(2)有同学认为先在A处产生白烟是因为HCl分子比NH3分子运动速度慢,请你分析影响分子运动速度的因素可能是__________________ 

(3)影响分子运动速率的因素还有温度,请举出生活中的一个实例____________

(4)该实验中的注射器也可改用胶头滴管直接滴入液体,相比较用注射器的优点是___________

答案

(1)固体;

(2)分子的质量大小或者相对分子质量大小(合理即给分);

(3)阳光下或者温度高衣服干得快,温度高水蒸发的快,糖在热水里比在冷水里溶解的快等;

(4)可以控制体积节省药品、可以减少气体挥发造成的污染等

单项选择题
单项选择题

Training as mental-health professionals is supposed to be "color blind". That sounds fine but in practice it means that people from black and ethnic groups get an unfair treatment because their particular problems are seldom acknowledged.

So a project was piloted involving Bangladeshi women in inner-city London, most of whom migrated to the UK in the 1960s and 1970s from a rural background. Many of these women turned to their doctors with common symptoms of anxiety, such as headaches, sleeping difficulties, loss of appetite and lack of energy. They were usually prescribed tranquillizers or even Vitamin C since the underlying causes remained, the women visited their doctors with increasing frequency and some were referred on to mental-health professionals.

The psychologists wanted to see how normal Western approaches to anxiety problems might work when applied across cultures. However, they found that many things in the standard approach had to be changed. They had to translate many of the usual examples—they would normally compare learning to relax with learning to drive, for instance, which would not have been culturally appropriate. At first they asked the women to rate, on a scale one to ten, the effect of relaxation on their level of anxiety. They found numbers an odd way of expressing how they were feeling. So psychologists shifted their focus to words and talked of five stages form "very good" to "very bad".

As it was a pilot project, there were shortcomings. Psychologists looked for too little back-up and did not collect as much objective data as they might have done with a white group. They fell into the white stereotype of assuming that Bangladeshi women would find the use of various checklists and written records foreign. Perhaps racism has conditioned the professionals to a greater extent than they expected. Psychologists found that using a Western model across cultures has potential. But it needs political, financial and personal commitment.

The standard approach to treating anxiety had to be changed because ().

A. the cultural background of the women was very different from the standard one

B. the Bangladeshis were exposed to racist harassment and language difficulties

C. the Bangladeshi women asked them to change it

D. the women could not relax