题目

There are many colors in nature. But do you know if a color has weight? I think you’ll say “no”. But I am afraid you are wrong. If you don’t believe, you may do a small experiment.First, put two objects with the same weight into two boxes. Then cover the box. Third, wrap one box with a red piece of paper, the other with a white piece of paper. OK. Now hold the boxes with your hand one by one. It is certain that you will think the red one is a little heavier.Why do you think so? A scientist found that different colors have different weight in a man’s mind. So he did man tests下列实验数据合理的是（ ）A．用pH试纸测得某地雨水的pH为5B．用10mL量筒量取了6.53mL水C．用20g氯化钠和l00g水配制的l20g食盐水，其溶质质量分数为20%D．用托盘天平称得某纯碱样品的质量为10.57g