一、评价实验方案型 例1 有人设计如图1所示的实验来验证质量守恒定律:把装有硫酸铜溶液的小试管放入盛有氢氧化钠溶液的烧杯中,将烧杯放到托盘天平上,用砝码平衡.取下烧杯并将其倾斜,两种溶液混合反应,反应后再把烧杯放到天平上,观察天平是否平衡. I. EVALUATION OF THE EXPERIMENTAL PROGRAM FORM 1 Someone has designed the experiment shown in Figure 1 to verify the law of conservation of mass: Place a small test tube containing a cupric sulfate solution in a beaker containing sodium hydroxide solution and place the beaker on a tray scale. On the balance, use a weight. Remove the beaker and tilt it. The two solutions mix and react. After the reaction, place the beaker on the balance and observe if the balance is balanced.