（1）现有34g某气体，它的摩尔质量为17g·mol-1。则：
① 该气体的物质的量为___________mol。
② 该气体所含分子数为___________NA。
③ 该气体在标况下的体积为___________L。
④ 该气体完全溶于500mL水后稀释到2L，物质的量浓度为___________mol·L-1。
（2）将100mL 0．5mol/L Na2CO3溶液加水稀释到250mL，稀释后c（Na+）=___________mol·L-1。
（3）___________gH2O中的O原子数目与标况下22．4LCO2中的O原子数目相同。
（1）①2；②2；③44.8；④1
（2）0.4
（3）36
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| A young man and an old man were waiting for a bus at a station. They sat next to each other."What's that in your bag?" asked the young man, pointing to the big bag beside the 1 "Money," answered the old man. The young man could 2 believe his own ears. "What?" he said to himself in surprise, "So much money? My God! How I 3 to be able to get so much money!" Then he began to think about how to get the money. The old man 4 tired and it seemed that he could hardly keep his eyes open. "Are you tired, sir?" asked the young man. "Then you'd better lie down on the chair and have a good rest. Don't worry about 5 . I'll wake you up in time." "All right. It's very kind of you, young man." The old man lay down and by and by (渐渐的) he fell asleep. The young man took the big bag carefully. 6 when he was just going to run away, he found a corner of his fur coat was 7 the old man's body. Several times he tried to pull it out, but he couldn't. At last he took off his 8 and went away with the bag. The young man ran out of the station as quickly as he 9 . He reached a place, where he thought the old man couldn't 10 him, then he stopped and quickly opened the bag. To his surprise, there was nothing but old newspapers in it. He hurried to the station at once. But when he got there, he found the old man had been away. | |||
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