问题 选择题

在常温下发生下列反应:①16H+ +10Z- +2XO4- =2X2+ +5Z2 +8H2O ②2A2++ B2 =2A3++2B- ③2B-+Z2 =B2+2Z-根据上述反应,判断下列结论中错误的是[ ]

A.溶液中可能发生:Z2 +2A2+=2A3+ +2Z-

B.Z2在①③反应中均为还原剂

C.氧化性强弱顺序为:XO4->Z2>B2>A3+

D.X2+是XO4-的还原产物

答案

答案:B

单项选择题
阅读理解

阅读理解。

Bicycle Safety

Operation  Always ride your bike in a safe, controlled manner on campus(校园). Obey rules and

regulations. Watch out for walkers and other bicyclists, and always use your lights in dark conditions.

Theft Prevention Always securely lock your bicycle to a bicycle rack---even if you are only away for

a minute. Register your bike with the University Department of Public Safety. It's fast, easy, and free.

Registration permanently records your serial number, which is useful in the possible recovery of the bike

stolen.

Equipment

              

Brakes Make sure that they are in good working order and adjusted properly.

              

Helmet A necessity, make sure your helmet meets current safety standards and fit

properly.

                

Lights Always have a front headlight---visible at least 500 feet in front of the

bike. A taillight is a good idea.

Rules of the Road

Riding on Campus  As a bicycle rider, you have a responsibility to ride only on streets and posted

bicycle paths. Riding on sidewalks or other walkways can lead to a fine. The speed limit for bicycles on

campus is 15mph, unless otherwise posted. Always give the right of ways to walkers. If you are involved

in an accident, you are required to offer appropriate aid, call the Department of Public Safety and remain

at the scene until the officer lets you go.

Bicycle Parking  Only park in areas reserved for bikes. Trees, handrails, hallways, and sign posts are

not for bicycle parking, and parking in such posts can result in a fine.

If Things Go Wrong

If you break the rules, you will be fined. Besides violating rules while riding bicycles on campus, you

could be fined for:

No bicycle registration---------------------------------------------------$25

 Bicycle parking banned--------------------------------------------------$30

 Blocking path with bicycle ---------------------------------------------$40

 Violation of bicycle equipment requirement -------------------------$35

1. Registration of your bicycle may help you _____________.

A. find y our stolen bicycle

B. get your serial number

C. receive free repair services

D. settle conflicts with walkers

2. According to the passage, what bike equipment is a free choice for bicycle riders?

A. Brakes.

B. A helmet.        

C. A headlight.      

D.A taillight.

3. When you ride a bicycle on the campus, ___________.

A. ride on posted bicycle paths and sidewalks

B. cycle at a speed of over 15 mph

C. put the walkers' right of way first    

D. call the police before leaving in a case of accident

4. If you lock your bicycle to a tree on the campus, you could be fined _________.

A. $25

B. $30

C. $35

D. $40

5 What is the passage mainly about?

A. A guide for safe bicycling on campus.      

B. Directions for bicycle tour on campus.

C. Regulations of bicycle race on campus.    

D. Rules for riding motor vehicles on campus.