Why do you exhale white gas in winter?

To tell you the answer, we will try it outdoors in winter, and we won't keep exhaling white air, especially during strenuous exercise. To illustrate this truth, let's do an experiment first. Jiang Yan kept putting it into a cup full of water and stirring it. The salt put in at first will melt, but if he puts in too much, it won't melt again. All kinds of phenomena are called saturation. The temper of air is the same as that of water. There is a certain limit to the water vapor contained in the air. The water vapor capacity of air is much smaller than that of hot air, so in very cold winter, the air exhaled in our mouths only contains water vapor air. If the shadow doesn't go in, those strange water droplets will condense into small water droplets and turn white when they meet cold.