下列何组物质是按酸、碱、盐顺序排列的（ ）
A．H2CO3、NaCl、Mg（OH）2
B．KOH、H2SO4、NaCl
C．MgSO4、NH3•H2O、HCl
D．HNO3、NaOH、Na2CO3
A、碳酸电离时生成的阳离子都是氢离子，属于酸；氯化钠是由钠离子和氯离子组成的化合物，属于盐；氢氧化镁是由镁离子和氢氧根离子组成的化合物，属于碱．故选项错误；
B、氢氧化钾电离时生成的阴离子都是氢氧根离子，属于碱；硫酸电离时生成的阳离子都是氢离子，属于酸；氯化钠是由钠离子和氯离子组成的化合物，属于盐．故选项错误；
C、硫酸镁电离时生成的镁离子和硫酸根离子，属于盐；氨水电离出的阴离子都是氢氧根离子，属于碱；盐酸电离时生成的阳离子都是氢离子，属于酸．故选项错误；
D、硝酸电离时生成的阳离子都是氢离子，属于酸；氢氧化钠电离时生成的阴离子都是氢氧根离子，属于碱；碳酸钠是由钠离子和碳酸根离子组成的化合物，属于盐．故选项正确．
故选D
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| I am taking my family to Europe this year. My wife and I and our two 1 are going. My brother is a farmer. He decided to go with 2 . First he is going on his horseback from his farm to the 3 station. Then he is taking a bus to our house. From here, we are going 4 . We are going to go by train to New York, and then take a ship to Europe. When we arrive in 5 , we are going to rent a car and 6 wherever we want to go. Then we are going to return the 7 . We are planning to fly home. It took us a long time to decide our 8 . At first we wanted to 9 to Europe because it was faster. But my brother prefers to take a 10 trip. The children like that too. |
| ( )1. A. horses ( )2. A. us ( )3. A. train ( )4. A. together ( )5. A. Australia ( )6. A. walk ( )7. A. ship ( )8. A. place ( )9. A. go ( )10. A. bus | B. dogs B. them B. railway B. back B. Canada B. run B. horse B. time B. fly B. train | C. sisters C. him C. bus C. over C. Russia C. drive C. bike C. trip C. come C. boat | D. children D. me D. underground D. again D. Europe D. ride D. car D. w ay D. run D. plane |