题目

同一短周期X、Y、Z三种元素，已知其气态氢化物分别是HX、H2Y、ZH3，则下列判断错误的是（ ）A. 热稳定性：HX＞H2Y＞ZH3 B. 还原性：HX＞H2Y＞ZH3C. 酸性：H3ZO4＜H2YO4＜HXO4 D. 非金属性：X＞Y＞Z 答案：【答案】B【解析】同一短周期X、Y、Z三种元素，其气态氢化物分别是HX、H2Y、ZH3，则从左到右分别为Z、Y、X，因为同周期从左到右元素非金属性增强，所以非金属性：X＞Y＞Z；非金属性越强，气态氢化物越稳定，故热稳定性：HX＞H2Y＞ZH3；非金属性越强，气态氢化物越不易失电子，还原性越弱，故还原  The Pacific island nation of Nauru used to be a beautiful place. Now it is an ecological disaster area. Nauru5 s heartbreaking story could have one good consequence—other countries might learn from its mistakes.    For thousands of years,Polynesian people lived on the remote island of Nauru,far from western civilization. The first European to arrive was John Feam in 1798. He was the British captain of the Hunter,a whaling ship. He called the island Pleasant Island.   However,because it was very remote,Nauru had little communication with Europeans at first. Then whaling ships and other traders began to visit,bringing guns and alcohol. These elements destroyed the social balance of the twelve family groups on the island. A ten-year civil war started,which reduced the population from 1,400 to 900.   Naum's real troubles began in 1899 when a British mining company discovered phosphate (憐酸盐) on the island. In fact,it found that the island of Nauru was nearly all phosphate,which is a very important fertilizer for farming. The company began mining the phosphate.    A phosphate mine is not a hole in the ground;it is a strip mine. When a company strip-mines,it removes the top layer of soil. Then it takes away the material it wants. Strip-mining totally destroys the land. Gradually,the lovely island of Nauru started to look like the moon.In 1968,Nauru became one of the richest countries in the world. Every year the government received millions and millions of dollars for its phosphate.   Unfortunately,the leaders invested the money unwisely and lost millions of dollars. In addition,they used millions more dollars for personal expenses. Some people realised that they had a terrible problem—their phosphate was running out. Ninety percent of their island was destroyed and they had nothing. By 2000,Nauru was almost financially mined. Experts say that it would take approximately $ 433,600,000 and more than 20 years to repair the island. This will probably never happen.36. What might be the author's purpose in writing the text?   A. To seek help for Naum's problems.   B. To give a warning to other countries.   C. To show the importance of money.   D. To tell a heartbreaking story of a war.37. What was Nauru like before the Europeans came?   A. Rich and powerful.   B. Modem and open.   C. Peaceful and attractive.   D. Greedy and aggressive.38. The ecological disaster in Nauru resulted from   A. soil pollution   B. phosphate overmining   C. farming activity   D. whale hunting39. Which of the following was a cause of Nauru^ financial problem?   A. Its leaders misused the money.   B. It spent too much repairing the island.   C. Its phosphate mining cost much money.   D. It lost millions of dollars in the civil war.40. What can we learn about Nauru from the last paragraph?   A. The ecological damage is difficult to repair.   B. The leaders will take the experts’ words seriously.   C. The island was abandoned by the Nauruans.   D. The phosphate mines were destroyed.    A special lecture began Thursday morning,given by a teacher aboard a space module about 340 km above her students on Earth,the first such attempt by Chinese.   Female astronaut Wang Yaping,one of the three crew members of Shenzhou X spacecraft,greeted about 330 primary and middle school students at a Beijing high school,through a live video feed system. uHello,everyone. I am Wang Yaping. I will host the lecture today”> she said,smiling towards the camera,on board of the space module Tiangong I.   The students on her class included children from migrant workers’ families,of ethnic minorities (少数 民族) and from Hong Kong,Macao and Taiwan. They were gathering at the High School Affiliated to Renmin University in Beijing. More than 60 million students and teachers at about 80 ,000 middle schools across the country were also watching the live broadcast on TV.   The first section of the class was all about weight. Nie Haisheng,commander of the crew,made a bit show of crossing his legs into a meditation (沉思、) sitting posture in the air,which only a martial art (武术) master could do in the movies but was impossible for real people on Earth. Thanks to the weightless condition,we are all masters,M Wang joked.   Then,Wang Yaping introduced the special scale on board of the orbiter,which was designed on basis of the Newton's second law of motion,or measuring the mass of an object through the net force and the acceleration.    The lesson was aimed at making space more popular,as well as inspiring enthusiasm for the universe and science,according to Zhou Jianping,designer-in-chief of China manned space program,who added that the lesson would also accumulate experience for similar larger activities.41. What's the best title for the passage?   A. Chinese Astronaut Gives the First Space Lecture   B. Students Watch Shenzhou X Spacecraft   C. What the Conditions Are like in Space   D. Ordinary People Act like Martial Art Masters42. The lecture given in space is intended for   A. students from Beijing   B. students from special areas   C. students all over the country   D. students interested in space module43. From the passage we can know that .   A. special training makes the astronauts stay in the air like martial art masters   B. astronauts are experiencing weightless conditions when in space   C. astronauts are showing to the students how they study and live in space   D. the Newton's second law of motion proves to be wrong in space 44. Why does astronaut Wang Yaping give the lecture in space?   A. To show us what weightless conditions are like.   B. To give a further explanation of weightlessness.   C. To show it is not easy to stay in space at present.   D. To make more of us interested in space science.