学术类雅思 (5分及以下) - 化学

(science) the smallest part of a chemical element that is found in the nature

原子

the smallest structure of a substance consisting of a group of atoms

分子

a substance that is composed of only one type of atom, typically characterized by specific physical and chemical properties

化学元素

a particle with a net electric charge due to loss or gain of one or more electrons

离子

(chemistry) a process in which several chemicals combine and form different substances

反应

(chemistry) a combination of two or more substances without forming a chemical bond or any chemical reaction

混合物

a water-soluble chemical substance that contains Hydrogen and has a sour taste or corrosive feature with a PH less than 7

酸性物质

(chemistry) a substance that can accept protons, donate electrons, or release hydroxide ions in aqueous solution

基础

the state of a substance that is neither solid nor liquid

气体形式

a substance such as water that flows freely, unlike a gas or a solid

液体

the state of a substance that is firm and has a certain shape, not like gas or liquid

to make something change from a particular state, condition or position to another

改变

a quantitive mesasure used for determining how acidic or alkanic something is on a scale of 0 to 14

酸碱度