1. 化合價，原子價原子或原子團(tuán)與其它原子反映時由所失、增加成共享的電子數(shù)目決定的化合能力
   The combining capacity of an atom or a radical determined by the number of electrons that it will lose, add, or share when it reacts with other atoms.
2. 五氧化物由五個氧原子和其它元素或基組成的化合物
   A compound having five atoms of oxygen combined with another element or radical.
3. 聚合物許多天然和人工合成的化合物中的任一種，通常具高分子的重量，包含最多可達(dá)上百萬個的彼此重復(fù)且相連的單位，每一個單位都是一個相對較輕和較簡單的分子
   Any of numerous natural and synthetic compounds of usually high molecular weight consisting of up to millions of repeated linked units, each a relatively light and simple molecule.
4. 氫與氧化合成水。
   Hydrogen and oxygen combine/Hydrogen combines with oxygen to form water.

化的英語翻譯：

合的英語翻譯：