题目

“Life is speeding up. Everyone is getting unwell.”This may sound like something someone would say today. But in fact, an unknown citizen who lived in Rome in AD 53 wrote it.We all love new inventions. They are exciting, amazing and can even change our lives.But have all these developments really improved the quality of our lives?Picture this: You’re rushing to finish your homework on the computer. Your mobile phone rings, a QQ message from your friend appears on the screen, and the noise from the television is getting louder and louder. Suddenly the computer goes blank and you lose all yKCl是一种常用的钾肥，其溶解度如下表。下列说法正确的是(      ) 温度／℃ 0 20   40 60 溶解度／g 27． 6 34．0 40．0 45．5 A．KCI饱和溶液中不能再溶解其他物质 B．20℃时，100 g KCl饱和溶液中含KCI 34．0 g C．40℃时，KCl饱和溶液的质量分数为40．0％ D．60℃的KCl饱和溶液降温至20℃，有晶体析出