题目

下列离子方程式正确的是 A． 小苏打治疗胃酸过多： HCO +H+ =H2 O+CO2 ↑ B． 铝粉投入氢氧化钠溶液中： Al+2OH- =AlO +H2 ↑ C． 使用漂白粉时为了增强漂白能力向漂白粉溶液中加入少量白醋： ClO- +H+ =HClO D． 过量硫酸氢铵与氢氧化钡反应： Ba2+ +2OH- +SO +2H+ =BaSO4 ↓+2H2 O 答案：AD【详解】 A．小苏打治疗胃酸过多，碳酸氢钠与盐酸反应生成氯化钠、二氧化碳和水： HCO +H+ =H2 O+CO2 ↑， A正确； B．铝粉投入氢氧化钠溶液中生成偏铝酸钠和氢气： 2Al+2OH- +2H2 O =2AlO +3H2 ↑， B错误； C．使用漂白粉时为了增强漂白能力向漂白粉溶液中加入少量白醋，白醋为弱酸， ClO- +CH3 阅读理解。     Somali pirates (海盗) robbed three Thai fishing ships with 77 sailors on board nearly l,200 Miles off the Somali coast, the farthest-off-shore attack to date, an officer said Tuesday.      Pirates have gone farther south and east in answer to increased patrols (巡逻) by warships off the Somalishore. The robbing of the three ships Sunday was about 600 miles outside the normal operation area for the international force, said a spokesman.      The spokesman said the attack so far out at sea was a clear sign that the international patrols against pirateswere having a "marked effect on pirate activity in the area".      "Once they start attacking that far out, you're not even really talking about the Somali basin or areas of waterthat have any connection with Somalia," said an officer, Roger Middleton. "Once you're that far out, it's just the Indian Ocean, and it means you're looking at trade going from the Gulf to Asia, from Asia to South Africa."      "This is the farthest robbing to date. They are now operating near the Maldives and India," said another officer.      The three ships-the MV Prantalay l l,12, a nd l 4-had 77 members on board in total. All of them are Thai,the spokesman said. Before the Sunday robbing, pirates held l l ships and 228 sailors.      Pirates have increased attacks over the past year in hopes of catching more dollar payments. Because of increased patrols and defenses on board ships, the success rate (率) has gone down, though the number of successful attacks has stayed the same year over year. 1. The pirate attack reported in the text happened _____. [     ]A. far out in the Indian OceanB. in the normal patrol areaC. near the Somali, coast D. in the south of Africa 2. According to the text, which can best describe the situation of the pirate problems? [     ]A. More goods on board are lost. B. Pirate attacks happen in a larger area now. C. The number of attacks has stayed the same these years. D. Pirate attacks are as serious as before along the Somali coast. 3. Which is true about the warship patrols according to the text? [     ]A. The patrols are of little effect. B. The patrols are more difficult. C. More patrols are quite necessary even in Asia. D. The patrols only drive the pirates to other areas. 4. How many sailors were held by the pirates up to the time of the report? [     ]A. 228. B. 77. C. 383. D. 305.