题干

阅读下列短文,从每题所给的四个选项 A、B、C、D中选出最佳选项。

B

    MSG (monosodium glutamate) is a food additive (食品添加剂), which has been widely used by many food factories all over the world since it appeared first in Japan in 1909.

    MSG is a substance that is added to some food to improve its original (原先的) taste and colour. It is used in foods around the world such as cakes, bread, frozen meats, fish and vegetables. In the beginning, people thought MSG was safe just like salt and sugar. However, in 1968 some people reported they seemed to have bad reactions (反应) to MSG after having had a meal at a restaurant. They included headaches and quick heartbeat (心跳). It was also reported that MSG excited a person's brain and caused his death in Japan. Scientists think that MSG may lead to many neurological disorders (神经紊乱). In mice studies done by a university, the evidence showed the mice didn't want to eat the food including MSG.

    Today many food companies "hide" MSG on food labels (标签) by using different names. If you see "natural flavorings", "hydrolyzed protein" and "spices" in a food label, you are probably seeing a hidden way to "report" MSG in a food label. Every time we have a meal in a restaurant, we always feel the food very delicious to taste, but sometimes it is dangerous for our health because some poisonous food additives have been added to the food.

    To protect people's health, our governments, from central to local, are taking actions to stop factories producing poisonous food additives.

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合理地开发和利用资源、能源,节能减排,保护环境,是人类社会可持续发展的基础.氢气是理想的能源之一,科学家最近研制出利用太阳能产生激光、并在二氧化钛( TiO2)表面使海水分解得到氢气的新技术.

(1)水分子分解时,断裂的化学键是H﹣O键,此时需要____ (填“放出”或“吸收”)能量.水分解生成氢气和氧气的反应属于____ (填“放热”或“吸热”)反应.

(2)氢气是理想的清洁燃料的原因主要有:一是其完全燃烧放出的热量是等质量汽油完成燃烧放出热量的3倍多,二是制取它的原料是水、资源不受限制,三是它____ ,不会污染环境.生物质含有葡萄糖、淀粉和纤维素等糖类,也称碳水化合物,绿色植物将二氧化碳和水变成碳水化合物的过程称为____ 

(3)氢能开发的首要问题是研究如何以水为原料制取氢气.下列有关制取氢气的研究方向可行的是____ (填字母).

a.组成水的氢、氧都是可燃的,可以研究在水不分解的情况下,使氢气成为燃料

b.寻找高效的催化剂,使水分解产生氢气,同时释放出热量

c.寻找特殊化学物质,用于开发廉价能源,以分解水制取氢气

d.寻找更多的化石燃料,利用其燃烧放热,使水分解产生氢气

(4)汽车或某些工业生产的尾气中含有的氮氧化物NOx(即NO和NO2的混合物),对生态环境和人类健康带来较大的威胁.

①大量的氮氧化物排放到空气中会导致的主要环境问题有形成酸雨、____ (填﹣项).

②已知在催化剂和加热条件下,NO与NH3反应的化学方程式为:6NO+4NH35N2+6H2O

某研究小组按下列过程探究不同催化剂对NH3还原NO反应的催化性能:

若控制其他实验条件均相同,在催化反应器中装载不同的催化剂,将经催化反应后的混合气体通入滴有酚酞试液的稀硫酸溶液(溶液的体积、浓度均相同).为比较不同催化剂的催化性能,需要测量并记录的数据是____ 

③工业上常用Na2CO3溶液吸收处理某些尾气中的NOx.己知:

NO不能直接与Na2CO3溶液反应;

NO+NO2+Na2CO3═2NaNO2+CO2

2NO2+Na2CO3═NaNO2+NaNO3+CO2

则当NOx被Na2CO3溶液完全吸收时,x的取值范围是____