一定条件下，在体积为2L的密闭容器中，3molX和3mol Y发生反应：3X（g）+Y（g）2Z（g），经60s达到平衡，生成0．4mol Z。下列说法正确的是                       （   ）

A．60s内反应速率为（X）=0．05 mol／（L·s），X的转化率为80％

B．其它条件不变，将容器体积变为4L，Z的平衡浓度变为原来的

C．其它条件不变，若升高温度，X的体积分数增木，则该反应的△H>0

D．其它条件不变，若初始投入2mol X和2mol Y则物质Y的转化率减小

一定条件下，在体积为2L的密闭容器中，3molX和3mol Y发生反应：3X（g）+Y（g）2Z（g），经60s达到平衡，生成0．4mol Z。下列说法正确的是                       （   ）

A．60s内反应速率为（X）=0．05 mol／（L·s），X的转化率为80％

B．其它条件不变，将容器体积变为4L，Z的平衡浓度变为原来的

C．其它条件不变，若升高温度，X的体积分数增木，则该反应的△H>0

D．其它条件不变，若初始投入2mol X和2mol Y则物质Y的转化率减小

Stress is everywhere in our everyday life. Not only men have it, but also women and young people.

The most important reasons of stress are: death, diseases, exams, making money, getting married, moving houses, changing jobs, ending friendships and so on.

How do you know whether you have stress or not? Could you give your answers to the following questions?

Stress Test

Do you...	Yes	No
Easily get angry?
Often sleep badly?
Get headaches a lot?
Take medicine to help sleep?
Find it difficult to relax?
Usually hide your feeling?
Smoke and drink a lot to keep quiet?
Find it difficult to put your heart into something?

If your answer "Yes" to more than two of these questions, you are one of those people with stress. So what can you do about it?

Doing relaxing exercises, talking with friends and listening to light music are all usual ways of relieving (减轻) stress. However, doctors now say that there are easier ways-people should laugh and smile more often. When you laugh and smile, your body relaxes. They also say that people, especially men, should   X   more often, because crying is a natural way of relieving stress.

1.Which of the following is NOT the reason of the stress?

A. Taking exams.    B. Changing jobs.

C. Taking medicine to help sleep.     D. Making money.

2.According to the passage, which of the following is true?

A. Women and young people never have stress.

B. Stress is everywhere in our everyday life.

C. People who answer "No" to all of the questions have great stress.

D. People who answer "Yes "to more than two of the questions have no stress.

3."X" in the passage should be the word "      ".

A. cry             B. laugh           C. smile           D. smoke

4.The main idea of the passage is       .

A. about stress and how to relieve your stress

B. that there are many reasons for having stress.

C. that laughing and smiling more can help relieve your stress.

D. that doing the Stress Test is a good way to help you live a better life.

 

黑火药是我国四大发明之一，黑火药的爆炸可用以下式子表示其反应和生成物：2KNO₃＋3C＋SK₂S＋N₂＋3X，则X的化学式为________，如果你配制火药，那么KNO₃，C，S这三种原料的质量比是__________时，才能使火药燃烧最充分。