氧气是初中化学中介绍的三种重要气体之一,对氧气知识的考查是历年各地中考命题的热点,题型不断变化且设计新颖.现将近几年出现的题型归纳如下. Oxygen is one of the three important gases introduced in junior high school chemistry. The examination of oxygen knowledge is a hot topic in the propositions of various local examinations over the years. The question types are constantly changing and the design is novel. The types of questions that have emerged in recent years are summarized below.