题目

日本福岛3.12地震后，可用二氧化氯（ClO2）来作消毒剂。用氯酸钠（NaClO3）和盐酸反应可制得二氧化氯，反应方程式：2 NaClO3 ＋ 4HCl ＝ 2 ClO2↑＋ Cl2↑ ＋ 2X ＋ 2 NaCl ,请推断出X的化学式为 A、HClO    B、NaOH     C、H2O     D、HClO3 答案：C四、阅读理解（40分）Learning online should make use of a number of Internet tools: e-mail lets you exchange letters between continents very cheaply and almost immediately. Large groups of people can share their discussions by using electronic lists to send every letter to everyone on the list. Electronic magazines bring you up-to-date topics, such as news, arts, and sports. Search engines allow you to look for anything you want on the Internet, including the holdings of major libraries. In a chat room you can have a real-time written talk. Audio and video bring the world to your computer -— you can listen to the world's radio stations, watch the evening news from another continent. And in an online conference you can even talk to your teacher and fellow students abroad.Do you have e-mail? How much do you communicate with your friends over the Internet? Internet, the newest child in technology, is like a modern communication highway. It's also a kind of super-shop, almost anything you can buy in a store -— you can get it through Internet, without leaving home at all.56. What is the passage mainly about?A. Internet    B. Radio stations    C. Magazines    D. Libraries57. What is the quickest and cheapest way of getting in touch with your friend abroad?A. By telegraph                 B. By air-mail C. By e-mail                    D. By telephone58. Which of the following will you choose if you want to hold a meeting over the Internet?A. Chat room                   B. Search engines  C. Online conference             D. Electronic lists59. In the writer’s opinion, it can be inferred that we might work _____ in the future.A. in the office                  B. at home    C. at the library                 D. in the store