液化

1. Origins, structure, and basic meaning

• Structure: 液化 is read as えきか and is a noun and する verb for liquefaction, the change of a substance into a liquid state.
• Basic usage: A cooled gas liquefying appears in 気体が冷やされて液化する, while collecting a liquefied substance appears in 液化した物質を集める.

2. Common pitfalls and similar expressions

• A change and the resulting state
  • The process of becoming liquid is expressed with 液化する, while material that has already changed is 液化した物質.
• Difference from 溶ける
  • 溶ける is used when a substance melts or dissolves, while 液化 technically describes a change such as the gas-to-liquid process in the example.