题目

The Winner’s Guide to Success Do you know what makes people successful? To find out the answers, an American scholar recently visited some of the most successful people around the world. 36  Be responsible for yourself Sometimes you may want to blame others for your failure to get ahead. In fact, when you say someone or something outside of yourself is stopping you from making success, you’re giving away your own power.37  Write a plan It is very difficult to try to get what you want without a good plan. It is just like trying to drive through strange roads to a city far away.11．致冷剂是一种易被压缩、液化的气体，液化后在管内循环，蒸发时吸收热量，使环境温度降低，达到致冷目的．人们曾采用过乙醚、CH3Cl等作致冷剂，但它们不是有毒，就是易燃．于是科学家根据元素性质的递变规律来开发新的致冷剂．据现有知识，某些元素化合物的易燃性、毒性变化趋势如下：（1）氢化物的易燃性：第二周期CH4＞NH3＞H2O＞HF；第三周期SiH4＞PH3＞H2S＞HCl．（2）化合物的毒性：PH3＞NH3 H2S＞H2O；CS2＞CO2CCl4＞CF4（选填＞或＜）．于是科学家们开始把注意力集中在含F、Cl的化合物上．（3）已知CCl4的沸点为76.8℃．CF4的沸点为-128℃．新致冷剂的沸点范围介于其间．经过较长时间反复试验，一种新的致冷剂氟里昂CF2Cl2终于诞生了，其他类似的还可以是CFCl3或CF3Cl．（4）然而，这种致冷剂造成了当今的某一环境问题是使大气臭氧层出现空洞．但求助于周期表中元素及其化合物的a变化趋势来开发致冷剂的科学思维方法是值得借鉴的．①毒性②沸点③易燃性④水溶性⑤颜色a．①②③b．②④⑤c．②③④