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短周期元素X、Y、Z、M的原子序数依次增大，元素X的一种高硬度单质是宝石，Y2+电子层结构与氖相同，Z的质子数为偶数，室温下M单质为淡黄色固体，回答下列问题：

（1）M元素位于周期表中的第（）周期、（）族。

（2）Z元素是（），其在自然界中常见的二元化合物是（）。

（3）X与M的单质在高温下反应的化学方程式为（），产物分子为直线形，其化学键属（）共价键（填“极性”或“非极性”）。

（4）四种元素中的（）可用于航空航天合金材料的制备，其单质与稀盐酸反应的化学方程式为（）。

答案

参考答案：

（1）三；ⅥA

（2）Si；SiO2

（3）C+2SCS2；极性

（4）Mg；Mg+2HCl═MgCl2+H2↑

名词解释

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单项选择题

Vienna was one of the music centers of Europe during the classical period, and Haydn, Mozart, and Beethoven were all active there. As the (1) of the Holy Roman Empire (which included parts of present-day Austria, Germany, Italy, Hungary, Czech and Slovakia), it was a (2) cultural and commercial center (3) a cosmopolitan character. Its population of almost 250,000 (in 1800) made Vienna the fourth largest city in Europe. All three (4) masters were born elsewhere, but they were (5) to Vienna to study and to seek (6) . In Vienna, Haydn and Mozart became close friends and influenced each other’s musical (7) . Beethoven traveled to Vienna at sixteen to play for Mozart; at twenty-two, he returned to study with Haydn.

Aristocrats from all over the Empire spent the winter in Vienna, sometimes bringing their private (8) . Music was an important part of court life, and a good orchestra was a (9) of prestige. Many of the nobility were excellent musicians.

Much music was heard in (10) concerts where aristocrats and wealthy commoners played (11) professional musicians. Mozart and Beethoven often earned money by performing in these intimate concerts. The nobility (12) hired servants who could (13) as musicians. An advertisement in the Vienna Gazette of 1789 (14) : " Wanted, for a house of the gentry, a manservant who knows how to play the violin well. "

In Vienna there was also (15) music, light and popular in (16) . Small street bands of wind and string players played at garden parties or under the windows of people (17) to throw (18) money. Haydn and Mozart wrote many outdoor entertainment (19) , (20) they called divertimentos or serenades. Vienna’s great love of music and its enthusiastic demand for new works made it the chosen city of Haydn, Mozart and Beethoven.

18（）

A.off

B.away

C.about

D.down
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