题目

     A city child’s summer is spent in the street in front of his home, and all through the long summer vacations I sat on the edge of the street and watched enviously the other boys on the block play baseball. I was never asked to take part even when one team had a member missing—not out of special cruelty, but because they took it for granted I would be no good at it. They were right, of course.      I would never forget the wonderful evening when something changed. The baseball ended about eight or eight thirty when it grew dark. Then it was the custom of the boys to re7．NA表示阿伏加德罗常数的值，下列叙述正确的是（　　）A．1molFeCl3与沸水反应生成NA个Fe（OH）3胶粒B．物质的量浓度为0.5 mol/L的MgCl2溶液中，含有Cl-个数为1NAC．25℃，1.01×105Pa，11.2L Cl2含有的分子数小于0.5NAD．常温下，23 g NO2含有2NA个氧原子