碘量法是利用碘的氧化性和碘离子的还原性来进行滴定分析的分法。

现代心理咨询起源于美国的职业指导运动。 ( )

空气是一种十分重要的天然资源。

(1)空气的成分按体积计算，含量最多的是________(填写分子式)；空气属于混合物，其理由是_____________________________________________________。

(2)拉瓦锡用金属汞通过定量的方法研究了空气的成分，写出该实验中发生的一个反应方程式_______________________________________。

(3)工业上用分离液态空气的方法制备氧气，这一过程属于___________(填“物理”或“化学”变化)；实验室可通过多种途经制取氧气，如分解过氧化氢、加热氯酸钾和二氯化锰、加热高锰酸钾、电解水等，从减少能量耗用 (“低碳”)上思考，你选择的实验室制取氧气的方法是____________________。

(4)下列物质能在氧气中燃烧，但不能在空气中燃烧的是_____________；

A．红磷 B．木炭 C．铁丝 D．硫

(5)煤是一种常用的化石燃料，通常情况下，堆在露天的煤没有燃烧，是因为______________________；煤和石油等化石燃料燃烧会造成对空气的污染，需要使用和开发新能源，如氢能(氢气)，还有你熟悉的新能源是________________ ；                               (举出两种即可)。

治疗空肠弯曲菌性肠炎首先选择下列哪种药物（）

A.头孢曲松

B.氨苄西林

C.庆大霉素

D.喹诺酮

E.红霉素

从人体呼出的气体可以使（　　）

①带火星的木条复燃；②澄清的石灰水变浑浊；③燃着的木条燃烧更旺；④燃着的木条能继续燃烧．

A．①③

B．②④

C．①②

D．③

You may never connect the words “good” and “eco-friendly”with plastic.It’s time to do a rethink on that as we say hello to hemp(大麻)plastic.Traditionally,plastics have been made from petrochemicals,which are mainly poisonous.Plants,on the other hand,are also a source of cellulose(纤维素),which can be used to make biodegradable (生物所能分解的)plastic.As hemp happens to be one of the richest sources of cellulose,it is only natural that scientists will support its use,considering its ecological benefits.

Hemp plastic is biodegradable and recyclable.If you thought being eco-friendly reduced its solidity,you couldn’t be more wrong.The hard level of hemp plastic can match that of regular plastic.Hemp plastic is resistant to heat;however,the most outstanding feature of a few varieties of hemp plastic is that they are flame resistant too.Finally,if Henry Ford could imagine creating a car with this material,we can perhaps believe that it indeed is“ten times stronger than steel”.

It is a pity that with so many useful qualities,we don’t see hemp plastic being used in our everyday life,the way it ought to be.Hemp plastic can easily take the place of the exiting plastic in products like cell phone chargers(充电器),laptop covers,etc.Currently,hemp plastic is being used to produce audio(音响设备),video,toys,automobile parts and packaging materials.

Hemp fiber is one of the strongest natural fibers known to us.As scientists keep looking for ways to solve the ecological damage that traditional plastics have caused,here is a material that can be produced to be 100% biodegradable.Hemp plastic is known to be several times durable as compared to polypropylene(聚丙烯)plastic,and it comes without all the health and safety threats,It really has long useful life.

Plastics keep reminding us of the damage that we have done to our planet,all under the excuse of convenience.As hemp products have become a new choice into our daily life,Please take a green plan now and make your effort to protect the environment.

小题1:Plastics produced in the traditional way are______.

A．harmful

B．made from plants

C．good and eco-friendly

D．biodegradable小题2:According to Para.2,hemp plastic_____.

A．is all resistant to flame

B．doesn’t have enough solidity

C．will take the place of steel

D．can be used again after being processed小题3:What does the underlined word“durable”mean in Para.4?

A．Very useful of important.

B．Costing little money or less money.

C．Staying in good condition for a long time.

D．Existing in large numbers or in many places.小题4:Which aspect of hemp plastic isn’t mentioned in the passage?

A．Features.

B．Production cost

C．Applications.

D．Advantages.小题5:What can we know from the passage?

A．Using hemp plastic is inconvenient.

B．People haven’t made the most of hemp.

C．Hemp fiber is a kind of strong man-made fiber.

D．Scientists have already known how to solve ecological damage.