问题 选择题

0.05 mol某金属单质与足量的盐酸反应,放出1.12L H2(标准状况),并转变为具有Ar原子的电子层结构的离子,该金属元素在元素周期表中的位置是:(      )

A.第三周期第IA族

B.第四周期第IA族

C.第三周期第ⅡA族

D.第四周期第ⅡA族

答案

答案:D

1.12L H2,所以转移电子的物质的量为0.05mol×2=0.1mol。根据得失电子守恒可知金属的化合价为,又因为金属离子具有Ar原子的电子层结构,所以该金属的原子序数为18+2=20,即为钙元素。所以答案是D。

阅读理解

Speaking of Copenhagen, what do you think of? The little Mermaid, the fairy tale writer H.C. Anderson, the COP15 meetings , or a city where people bike even though they have cars.

When landing on Copenhagen Tasstrup Airport, you can see numbers of white propeller generators standing in the blue waterfront. The constant moving paddles are producing renewable energy to the city. During the recent Climate Change Conference, the city was introduced to the world as an example of climate-friendly city. Evidences other than wind power stations were obvious everywhere.

While private cars can be a great source of pollution in other cities, the main form of transport in the capital of Denmark is, however, public transportation. By public transportation, I mean one of very good quality. Buses are usually Volvo and most of the traffic lights are of Siemens. Additionally, buses, metros and intercity-trains (named S-train) are well equipped, constantly maintained, special and good-looking. The seats in the trains are of sofa-designed. Sticky gum or dirty spot rarely appear. Thanks to a small population, it is much easier to maintain the condition of the vehicles. Free wireless internet service is provided in S-trains. Seats are always possible even at rush hours if the passenger is patient enough to look for it. Taking the convenience for granted, Danish people find it hard to imagine how the metro in Tokyo can be as crowded as a “sardin can”. Pets and baby-wagons are allowed in buses, subways and S-trains. All the facilities enable better service to bigger passenger group. It is also notable that the mass transit uses green fuels and electricity.

Cars are common in Copenhagen, but people have an alternative of short distance transport: bikes. Denmark is known as bike-friendly for many reasons, such as flat land, splendid cycle ways, and the Danish fond of motion. But please be aware that riding a bike in Copenhagen is not like biking in Beijing. First of all, it is quite speedy. Many people ride to work every morning. Punctuality is important and they have to ride as fast as possible to be on time. So why not speed up? Not my philosophy. As a result, I am often hastened by impatient riders who unfortunately piled up after me. Second, considering the speed, bike helmets, front and back lights and other necessary accessories are required. Riders need to set a white light in the front of the bike and red light at the back. One may end up with a big fine if not riding with them.

72. In the passage we get to know that _____.

all energy come from wind power stations

different kinds of green energy keep this city running

a lot of electricity is imported from other countries

people in this city use little energy

73. S-trains are a kind of transportation______.

A. which send their passengers from one city to another.

B. which uses wind to run their ways

C. which is the only way for you to go from one city to another.

D. which you are not allowed to take if you take a pet.

74. In the last paragraph what does “Punctuality” mean?

A. Being fit         B. Not being scolded       C. Not being late      D. Speeding

75. In Copenhagen if you ride too slow ,_____

A. you will be fined by police.

B. it means that you need to buy a better bike.

C. you may block the traffic flow.

D. many bike riders will shout at you.

单项选择题

Burkina Faso student teacher Hema Cecile has a lot more time to crack the books thanks to a recent initiative from the World Bank and the International Finance Corporation (IFC). The launch of the Lighting Africa program by the two organizations this year has made it possible for Cecile to swap kerosene lamps for a solar-powered LED lantern.

Lighting Africa is a $12 million project which intends to bring light to the poorest regions across sub-Saharan Africa. The program works with the lighting industry to develop clean, affordable lighting and energy solutions for millions without access to electric grids. Its aim is to accelerate the market and to develop education programs that inform off-grid populations currently dependent on costly, inefficient and hazardous fuel-based lighting about modern alternatives.

Cecile used to spend $3-4 a month on kerosene for her lamp. That is a large proportion of her earnings—like 70 percent of the population she lives on less than $2 a day. In the weeks since buying her lantern she has managed to read four books including Madame Bovary. by Gustave Flaubert and Emile Zola’s Germinal. She is among the most learned in a society which has the world’s lowest literacy rate, according to a 2007 UN Human Development Report. When she graduates next year she will teach in a local junior school She makes ends meet by holiday jobs as a cleaner and an IT trainer. To earn her daily ration of cornmeal she does shifts from May to September in a corn field.

The lanterns are designed to look like the kerosene ones they are replacing in order to increase adoption among the population. Each has a small solar panel on the top and costs an average $30, although some cost $100, depending on the size of the battery and the number of LED lights it contains.

Because of the large number of sunlight hours in Burkina Faso, the lamps can be relied on to work whenever needed. The battery life is 2-4 years, and can be replaced once they lose their storage capacity. The LED lights last 5-10 years.

Although it is barely out of its trial period the project, Chabanne said there are signs the project is a boon for the population in areas other than household savings and education. "There are fewer people reporting eye problems to the local hospital.

Which one of the following statements is true about Cecile()

A. She is illiterate, just like many of the citizens in her region

B. She works only from May to September every year

C. She is a full time employee in an IT company

D. She is still a student now