一般来说,这种词汇的变换是受外来语词源影响.
solution:
[Middle English,from Old French,from Latin solti,soltin-,from soltus,past participle of solvere,to loosen; see solute.]
solve:
[Middle English solven,to loosen,from Latin solvere; see leu- in Indo-European roots.]
不过有这个词：
solvation
溶剂化
这是化学专用词汇.