倒扣在水中的容器内燃烧蜡烛的熄灭及相关现象的研究

Study on extinguishment and related phenomena of a burning candle in a inverted vessel over water

将一支蜡烛置于水中,点燃后在其上倒扣一只量筒,观察到倒扣量筒之后蜡烛逐渐熄灭,并伴随着量筒内水面的上升,进入量筒的水的体积约为其中气体体积的20%.我们从理论上分析了物理因素和化学因素对蜡烛熄灭和量筒内水面上升的影响,其中化学因素带来的量筒内气体体积的改变量约为3.2%-7.16%,认为液面上升最主要的原因是物理因素的贡献,即蜡烛燃烧放热导致空气从量筒中溢出,蜡烛熄灭后温度降低使量筒内外产生压强差所致.进一步设计实验证实了蜡烛熄灭后,由物理因素导致进入量筒内水的体积为原来量筒内气体体积的10.65%-12.98%,而化学因素带来的改变量不足2%,量筒内液面上升的主要原因为物理因素的贡献所致.

When a measuring cylinder is covered on a burning candle stand up into the water within a beak,extinguishing of the candle and rinsing up of the water in the cylinder are observed simultaneously.The volume of the water that enters into the inverted cylinder is about 20 percent of the volume of the original gas in it.We analyze the effects of physical and chemical contributed factors on the extinguishment of the candle and rising up of the water theoretically.The ratio of water volume entered into the inverted cylinder to the original gas volume in it contributed by chemical factors is about 3.2% to 7.16%.We attributed the ring up of the water in the cylinder to the contribution of physical factors.The heat from combustion of the candle leads to spilling of the gas out of the inverted cylinder,and pressure differences inside and outside the cylinder would be established after the candle extinguishes due to the lowering of the gas temperature.We set up experiments and measured the ratio of water volume entered into the cylinder after the candle extinguishing to the gas volume in the cylinder considering the contribution of physical and chemical factors respectively.The ratio contributed by the physical factors is from 10.65% to 12.98%,while the ratio contributed by the chemical factors is less than 2%.The rising of the water in the inverted cylinder is contributed by the physical factors.