日日人人_亚洲美女在线视频_av手机在线播放_国产大片aaa_欧美中文日韩_午夜理伦三级

 (安徽省馬鞍山二中2009屆高三第四次模擬考試E篇)

John Dalton was born in England in 1766，ten years before the U．S．Declaration of Independence was signed．His family lived in a small cottage．As a small child，John worked in the fields with his brother，and helped his father in a shop where they wove cloth. Most poor boys at that time received no education，but John was lucky to attend a nearby school In 1766，when only about one out of every 200 people could read．

    John was a good student and loved learning．His teachers encouraged him to study many things when he was twelve. He opened his first school in a nearby town，but there was little money．He had to close his schoo1．

    Three years later，he joined his older brother and a friend in running a school. John studied the weather and nature around him. He collected butterflies，snails and mites. He discovered he was colorblind and studied that,too．

    In 1793，John began to think about different elements and their composition. He had a theory that each element is made up of identical(完全相同的) atoms and that elements are different because each is made of different atoms．

    In 1808，Dalton published a book，which listed the atomic weights of many known elements．These formed the basis for the modern periodic table(元素周期表)．Not everyone accepted Dalton’ theory of atomic structure at the time．However，he had to defend it with more research．

    When John Dalton died in 1844，he was buried with honors in England．More 400,000 people viewed his body as it lay in state．As his final experiment，he asked that an autopsy(驗尸)be performed to learn the cause of his color-blindness：This was done，and proved the color-blindness was caused not by a problem with his eyes，but with the way his brain worked．Even in death, he helped expand scientific knowledge．

    Today．scientists everywhere accept Dalton’s theory of atomic structure．A simple country boy showed the world a new way of thinking about the universe and how it is made．

73．John Dalton’s first school had to be closed mainly because___________．

A．he was color-blind                  

B．his family lived in a small cottage

C．he had hardly enough money to run I  

D．he lacked experience

74．Which of the following descriptions about John Dalton is wrong?

    A．John found a cure for color-blindness

    B．As a student，John was outstanding

    C．John used to help with farm work

    D．In his book，presentation of the atomic weight of many known elements was of great importance.

75．From the passage we may conclude that______．

    A．John Dalton’s only contribution to science was his achievement in chemistry

    B．as a great educator，John Dalton established the basis for education in England

    C．John Dalton’s book about the elements enjoyed great popularity then

    D．John Dalton devoted his entire life to science