问题 选择题

短周期元素X、Y、Z在周期表中的位置如图所示,则下列说法正确的是(  )

A.Z一定是活泼的金属

B.Y的最高价氧化物的水化物是一种强酸

C.Z的最高价氧化物的水化物是强酸

D.1molY单质跟足量水反应时,有1mol电子发生转移

答案

三种元素在短周期中的不同周期,则X一定位于第一周期,且在周期表的右侧,则一定为He,根据其它两种元素的相对位置可知Y为F元素,Z为S元素,

A、X为He,Y为F,Z为S,三种元素都是非金属元素,故A错误;

B、Y为F元素,无正价,没有对应的含氧酸,故B错误;

C、Z的最高价氧化物的水化物是H2SO4,为强酸,故C正确;

D、Y的单质与水反应的化学方程式为2F2+2H2O=4HF+O2,F元素化合价由0价降低到-1价,则1molF2单质跟足量水反应时,有2mol电子发生转移,故D错误.

故选C.

选择题
阅读理解

COOL INVENTIONS

CHARGE ON THE GO

From school to band practice, the Venturi Eclectic is an Earth-friendly way to get where you want to go. This battery-powered, zero-emission(meaning it doesn’t pollute the air) vehicle runs mainly on renewable energy. Solar panels on the Eclectic’s roof absorb sun rays when you’re driving. On windy days, you can connect a machine to the car’s roof collects energy from the wind while you’re parked. The Eclectic’s top speed is 28 miles an hour; the battery lasts for 31 miles before it needs to be recharged. Zipping (迅速行进)round the neighborhood has never been better.

WATER CLOCK

Here’s an eco-friendly way to tell time: Simply fill the Bedol Water-powered Clock’s tank(箱)with water, add some lemon juice, and the clock will display the time without the need for environmentally harmful batteries. There are two sets of metal electrodes(电极)inside the water tank. Water contains ions(离子)that carry negative and positive charges. These ions complete a charge between the electrodes creating enough energy to power the clock. Just refill the tank every few weeks, and this clock will keep on ticking.

LAND ROCKET

Bloodhound SuperSonic Car (SSC) will be the first car to attempt to break the 1,000-mile-an-hour barrier. (The current record is 763 miles an hour.) a concept for now, the rocket-shaped car gets its initial push to 350 miles an hour from a jet engine. Then a rocket fires up, pushing the SSC past 1,000 miles an hour. In order to keep the car streamlined(流线型的)the driver lies back at a 45-degree angle.

COOL CAMERA

You’re having a blast at your friend’s birthday party. But when it’s time to bring out the cake, everyone crowds around, blocking your view. No worries. Throw the Triops into the air, and this clever camera captures the view from above. The Triops can take three pictures at once, each from different angles. You can also record sounds and command the Triops to start shooting whenever it hears that noise. That’s one smart camera.

1.According to the passage, the Venturi Eclectic______.

A.is popular with businessmen

B.is suitable for a long trip

C.can turn wind into energy

D.has only a little gas emission

2.What is the common characteristic of the Venturi Eclectic and the Bedol Water-powered Clock?

A.They don’t need batteries.

B.They are difficult to operate

C.They can be powered by water

D.They are environmentally friendly

3.The underlined phrase “having a blast” in the last paragraph means______.

A.looking at a picture     B.enjoying yourself    

C.blowing out a candle       D.recording sounds

4.Which of the following is TRUE according to the passage?

A.The Triops in sensitive to sounds.

B.The driver of the SSC must be of great size.

C.The color of the Bedol Water-powered Clock is like that of lemon

D.The SSC doesn’t have anything to do with a rocket actually.