应用化学专业英语课文翻译

1.3 THE PERIODIC LAW

周期律

In 1869, Dmitri Ivanovitch Mendeleev (1834-1907) of Russia and Lothar Meyer (1830-1895) of Germany independently published their periodic arrangements of the elements. Both of these periodic arrangements were based on increasing atomic weights.

译：1869年，俄罗斯的德米特里·伊万诺维奇门捷列夫（1834年至1907年）和德国的洛萨迈耶（1830至1895年）独立地出版了他们对元素的定期安排。这两个周期的安排都是以原子量的增加为基础的。

At the time of Mendeleev's periodic table, about 63 elements were known. The brilliance and foresightedness of this work can be seen by the fact that Mendeleev left spaces between certain elements in his original table and predicted that these spaces would be filled by the discovery of new elements. He left a space for an undiscovered element after calcium and called the element eka-boron; another space was left under aluminum, which he called eka-aluminum; and another space under silicon, which he called eka-silicon. The term “eka” comes from Sanskrit meaning “one,” which Mendeleev used to indicate that the missing element was one place away in his table from the element indicated. Mendeleev even went so far as to predict, with high accuracy, the physical and chemical properties of those elements yet to be discovered. The three elements above were, in fact, discovered within his lifetime. Scandium (atomic number 21) was discovered in 1879 by Lars F. Nilson(1840-1899) of Sweden, and was found to correspond in properties to eka-boron; gallium (31) was discovered in 1875 by Lecoq de Baisbaudran (1832-1912)，and was found to correspond to eka-aluminum; and ger-manium(32)was discovered in 1886 by C.A. Winkler (1838-1904)，and was found to correspond to eka-silicon. The amazing way in which Mendeleev's predictions were fulfilled is illustrated in Table 1.2 which compares the predicted properties of eka-silicon with those of germanium.

译：在门捷列夫的周期表中，大约有63种元素是众所周知的。事实上，门捷列夫在他表中已确定的元素中留有空位并且预测这些空位会被以后发现的新元素填满，由此可见这项工作的辉煌和前瞻性。

他在钙的后面留了一个空位给未知元素并称之为准硼；在铝的下面留了一个空位并称之为准铝；在硅的下面留了一个空位并称之为准硅。

术语“准”来自梵文，意思是“之一”，是门捷列夫用来表示他表中指定元素中缺失的一个地方的元素。门捷列夫甚至高精确度地预测了目前为止仍未被发现的元素的物理性质和化学性质。事实上，上面提到的三个元素在他有生之年就已经被发现了。钪（原子序号21）在1879年被瑞典的Lars F. Nilson(1840-1899)所发现，并证实它的属性符合硼；镓（31）在1875年被Lecoq de Baisbaudran (1832-1912)发现，并证实它的属性符合铝；锗（32）在1886年被C.A. Winkler (1838-1904)发现，并证实它的属性符合硅。门捷列夫的预测以一种惊人的方式实现了，如表1.2，比较了准硅预测的那些性质和锗的性质。

Mendeleev constructed his table by arranging the elements in order of increasing atomic weights. The elements were tabulated so that those with similar chemical properties fitted into columns to form family groups. This arrangement left vacant spaces for undiscovered elements.

译：门捷列夫通过以原子量增加的顺序来安排元素构建他的表。那些化学性质相似的元素被制成列表，形成了族。这样的安排给未被发现的元素留了空置空间。

Several modifications have been made to Mendeleev's table. First，a new family of elements, the noble gases, was discovered and added to the table. Also, it was observed that when the elements were listed according to increasing atomic weights, several discrepancies arose in the table. In the present table, for example, argon appears before potassium, even though the atomic weight of argon is greater than that of potassium. There is no mistaking that potassium should come after argon, because argon is certainly one of the noble gases and potassium behaves like the other alkali metals. There are two other places in the table where this type of deviation occurs.