住在海边的人都有这样的体会,每年入冬以后,陆地上的河流湖泊一般都会陆续结冰,而海面上往往到了深冬也照样波涛汹涌,海浪起伏。这是为什么呢?清水到零摄氏度时就会结冰,而含有杂质的水则很难结冰。海水中的盐类大约占35‰,而且大多以离子形式存在。离子在溶剂中不停地运动,它的速率远远大于水分子的运动速率。即使水温降到零摄氏度时,因为有离子的运动作用,水分子也不易形成晶体状态,所以海水不易结冰。只有 Everyone living in the seaside has such an experience. Every year after winter, rivers and lakes on land usually freeze one after another, while the sea often goes deep into the winter and the waves are still choppy. Why is this? Clear water to zero degrees Celsius will freeze, and impurities containing water is difficult to freeze. Salt in seawater accounts for about 35 ‰, and mostly in the form of ions. The ions move constantly in the solvent, at a much greater rate than the rate of movement of water molecules. Even when the water temperature drops to zero degrees Celsius, the water molecules are not easily crystallized because of the movement of ions, so the sea water is not easy to freeze. only