下列做法不正确的是（ ）
A．将浓硝酸保存在无色玻璃瓶中
B．蒸馏时，应使温度计水银球靠近蒸馏烧瓶支管口
C．加热后的试管不能立即用冷水冲洗，防止骤冷炸裂
D．进行蒸发时蒸发皿放在铁圈上直接加热，并用坩埚钳夹取
答案：A
题目分析：浓硝酸见光易分解，则将浓硝酸保存在棕色试剂瓶中，A不正确；蒸馏时温度计测量的是蒸汽的温度，应使温度计水银球靠近蒸馏烧瓶支管口，B正确；加热后的试管不能立即用冷水冲洗，防止骤冷炸裂，C正确；进行蒸发时蒸发皿放在铁圈上直接加热，并用坩埚钳夹取，D正确，答案选A。
点评：该题是中等难度的实验题，侧重对学生基础知识的巩固和检验，意在培养学生灵活运用基础知识解决实际问题的能力的培养，有利于调动学生的学习兴趣，激发学生的学习积极性，有助于提高学生的学科素养。
Read the following passage. Fill in the numbered blanks by using the information from the passage. Write NO MORE THAN THREE WORDS for each answer. While it is impossible to live completely free of stress, it is possible to prevent stress as well as reduce its effect when it can’t be avoided. The US Department of Health and Human Services offers the following suggestions for dealing with stress． Try physical activity When you arc nervous, angry or upset, try releasing the pressure through exercises or physical activity．Running, walking, playing tennis, or working in your garden arc just some of the activities you might try． Take care of yourself You should make every effort to eat well and get enough rest．If you easily get angry and cannot sleep well enough, or you're not eating properly, it will more likely that you will fall into stressful situation．If stress repeatedly keeps you from sleeping, you should consult a doctor． Make time for yourself Schedule time for both work and entertainment．Don't forget, play can be just as important to your overall well-being as work- You need a break from your daily routine to just relax and have fun．Go window-shopping or work on a hobby．Allowing yourself at least a half hour each day to do something you en Joy． Make a list of the things you need to do Stress can result from disorganization and a feeling that "there's so much to do, and not enough time"．Trying to take care of everything at once can be too much for you and as a result, you may not achieving anything．Instead, make a list of everything you have to do, then do one thing at a time, checking off each task as it is completed．Set out to do the most important tasks first． How to deal with stress
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