腌制食品中含有亚硝酸盐,它会影响健康及诱发癌症,但维生素C对亚硝酸盐的形成有阻挡

题型:填空题

问题:

腌制食品中含有亚硝酸盐,它会影响健康及诱发癌症,但维生素C对亚硝酸盐的形成有阻挡作用。有一 种设想:在含有亚硝酸盐(NaNO2)的腌制食品中加入过量的化肥氯化铵与其共热,生成无毒害的氮气、水和氯化钠,过量氯化铵在持续加热的情况下分解为氨气与氯化氢挥发,此时腌制食品便可以放心食用。

(1)写出这种设想中反应的化学方程式________________________________ 。

(2)评价这种方案,并简述理由:_________________________________。

(3)请提出一条减少食用腌制食品中亚硝酸盐含量的措施:_________________________________。

考点:食品添加剂的使用其他钠盐(氯化钠、硫化钠、氮化钠等)
题型:填空题

阅读理解。

     George and Carol were medical students at the same college and like many other college students,

they enjoyed playing jokes on people. Both of them smoked, but they knew that their professor was

strongly against it, because smoking was dangerous to one's health. One day they decided to play a

joke on their professor.

      At one of their medical lectures (讲座) there was always a skeleton (骨架模型) in the room so

that the professor could show the students the different bones in the human body.

      That afternoon. Carol and George put a cigarette (香烟) in the mouth of the skeleton that was

to be used for their next lecture.

     When the professor came in. he began talking and then noticed the cigarette. He went up to the

skeleton, took the cigarette out of its mouth and said. "You really should give them up, old boy. Look

what they're doing to you!"

1.What do the professor's words mean _______.

A. It's only a joke to put a cigarette into a skeleton's mouth.

B. He would persuade the skeleton to give up smoking.

C. Smoking is really dangerous. It may even cause death.

D. Students should not learn from the skeleton to smoke.

2. To whom did the professor really say these words?

A. To George and Carol only.

B. To the skeleton which he called "old boy".

C. Only to himself.

D. To all the students who attended his lecture.

3.The underlined word "they" in the passage means _______.

A. George and Carol

B. the students

C. the bones

D. cigarettes

4.What do you think of the professor?

A. Serious but humorous.

B. Honest and foolish.

C. Kind and polite.

D. Hard to get along with.

题型:填空题

下列关于冲脉的叙述,错误的是()。

A.冲为十二经之海

B.冲为血海

C.是气血运行的要冲

D.是人体妊养之本

E.冲脉为月经之本

题型:填空题

以下属于现代认识论的哲学形态有()。

A.经验论

B.唯理论

C.观念论

D.实在论

题型:填空题

弹性模量

题型:填空题

TOSI锅炉正常运行时,过热蒸汽压力应保持在()MPa。

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