利用天然的雪可做很多实验。我们用它和食盐混合,作为冷却剂来液化某些气体。并把液化了的气体设法长期保存下来这是很有意思的。我在去年冬天曾经用雪作冷却剂液化了二氧化硫,并且把液态二氧化硫封入玻管中一直保存到今天。二氧化硫很容易液化,它在-10℃时是无色透明的液体。因此,用雪(或冰)与食盐混合作为冷却剂很容易把它液化。可是在夏天这样实验就很难成功,因为冰和食盐混合时很难得到较低温度。即使得到一些 Use of natural snow can do a lot of experiments. We use it mixed with salt, as a coolant to liquefy some gases. It is very interesting to try to save the liquefied gas for a long time. I liquefied sulfur dioxide with snow as a coolant last winter and sealed it in glass tubes until today. Sulfur dioxide is very liquefiable, it is a colorless and transparent liquid at -10 ° C. Therefore, it is easy to liquefy snow (or ice) by mixing it with salt as a coolant. However, such experiments in the summer is very difficult to succeed, because it is difficult to get a lower temperature when mixing ice and salt. Even get some