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问题 选择题

下列物质不会使人中毒的是（　　）

A．一氧化碳

B．甲醇

C．氯化钠

D．亚硝酸钠

答案

A、一氧化碳与血红蛋白结合会使人缺氧窒息死亡，故A错误；

B、甲醇有毒，能使人体失明，甚至使人丧命，故B错误，

C、氯化钠具有咸味，常用作调味品，故C正确；

D、亚硝酸钠有毒，误食引会起中毒引起人体中毒，故D错误．

故选C．

单项选择题

下列面食中，不属于“山西四大名面”的是( )。

A．臊子面

B．刀削面

C．拉面

D．拨鱼儿
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阅读理解
阅读理解
                                                                
                                                              The Scientific Method
     Did you ever wonder why the water level in a glass doesn't change when the ice in the glass melts
(融化)? To find out why, you can use the scientific method. Used by scientists in various situations, the
scientific method is also a clear and logical way to solve many real-world problems, as the procedure
below indicates.
Steps in the Scientific Method Examples
State the problem or question."Why doesn't the water level in a glass rise when ice melts?"
Collect information about the problem,
using  your own observations and
research.		You already know that ice is frozen water. From your research,
you learn that water and ice are made of water molecules (分子).
"Form a hypothesis, or a best guess
based on the information."		The molecules in water appear to be closer together
than they are in ice.
Test the hypothesis by doing an
experiment.		Fill four glasses with ice. Then pour water over the ice and fill
each glass to the rim. As the ice melts, you observe that the water
does not spill over the top of the glasses. Each time you repeat the
experiment, you get the same results.
Draw a conclusion based on your results.Molecules are closer together in water than they are in ice.
  
1. We all know the fact that        .
A. the water level in a glass doesn't change when the ice in the glass melts
B. the water level in a glass changes when the ice in the glass melts
C. the water level in a glass rises when the ice in the glass melts
D. the water level in a glass goes down when the ice in the glass melts
2. Which of the following is another good title for this passage?
A. Research and Conclusion            
B. Observation and Experiment
C. Follow the Steps to Find Out Why      
D. Mix Water with Ice and Get the Result
3. A hypothesis is _______.
A. a guess about the cause of something    
B. the first step in the scientific method
C. a conclusion about water molecules    
D. an experiment on ice and water
4. This passage suggests that _______.
A. repeated experiments lead to the right result  
B. research should be done in various situations
C. your hypothesis can prove your experiment results
D. a logical method is needed when solving problems
5. The chart in the passage is useful because it _______.
A. shows a diagram of how ice melts    
B. shows steps and examples
C. compares water with ice            
D. explains cause and effect
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