The volume of a solution of a salt is generally less than the sum of the unmixed volumes of the salt and the water, because of the tight packing of water molecules in the salvation shell around the ions.

• 盐溶液的体积一般都小于未混合时盐的体积与水的体积之和，因为水分子紧密地堆积在离子周围的溶剂化层中。