题目

下列有关二氧化碳的检验、制备和用途能达到目的的是(   ) A．干冰用于人工降雨 B．二氧化碳气体通入紫色石蕊试液中，溶液变为蓝色 C．用块状石灰石和稀硫酸迅速制备大量二氧化碳 D．将燃着的木条伸入集气瓶，火焰立即熄灭，证明瓶内原有气体就是二氧化碳 答案：A 【详解】 A、干冰易升华吸热，使周围温度降低，常用于人工降雨，故A正确； B、二氧化碳气体通入紫色石蕊试液中，二氧化碳与水反应生成碳酸，碳酸能使紫色石蕊试液变红，故B错误； C、石灰石和稀硫酸反应生成的硫酸钙微溶于水，覆盖在石灰石的表面，阻止了反应的继续进行，反应会渐渐停止，    In 1909 an English newspaper offered ?? 1,000 to the first man to fly across the English Channel in an aeroplane. Today, modern jets cross it in minutes. But at that time it still seemed a good distance. The race to win the money soon became a race between two men. Both were very colourful.     One was Louis Bleriot. He owned a factory in France that made motor car lamps. He was already well known as a pilot because he had had accidents several times. Some people laughed at him. One man said, “He may not be the first to fly across the Channel but he will certainly be the first to die in an accident!” But Bleriot was really a good and brave pilot. He also had many good ideas about aeroplane design.     The other man was Hubert Latham. He was half French and half English. He took up flying when his doctors told him he had only a year to live. “Oh, well,” he said, “if I’ m going to die soon, I think I shall have a dangerous and interesting life now.” Latham was the first to try the flight  across the Channel. Ten kilometres from the French coast, his plane had some trouble. It fell down into the water and began to sink under the water. A boat reached Latham just in time. He was sitting calmly on the wing and was coolly lighting a cigarette. Bleriot took off six days later. He flew into some very bad weather and very low cloud. He somehow got to the English side and landed in a farmer’s field. When he did so, a customs (海关) officer rushed up to his plane. Planes have changed since then, but customs officers have not. “Have you anything to declare(报关)?” The officer demanded. Bleriot was well known as a pilot because ____ .    A. he was unusually brave    B. he was quite rich    C. he had many good ideas about aeroplane design    D. he had had a few accidents Why did Hubert Latham want to fly across the Channel?    A. He thought he could manage it easily.    B. He wanted to be the first one to cross the Channel.    C. He knew he only had a year to live.    D. He had always been interested in flying. Which of the following is NOT true?    A. Latham became a pilot on the doctor’s advice.    B. He was told he could live another year.    C. His plane had some trouble.    D. He was saved by a boat when his plane was sinking.