The chemical meaning of 2h is two hydrogen atoms. Hydrogen atom is the atom of hydrogen element. The hydrogen atom model is electrically neutral, and the atom contains a proton with positive valence and an electron with negative valence, which are bound in the atom by Coulomb's law. Academic education refers to the educational form in which the educated enter schools or other educational institutions approved by the relevant departments of the state through national education examinations or other admission methods stipulated by the state and obtain academic certificates recognized by the state. According to the education laws and policies, according to whether the educated have obtained the diploma recognized by the state, the forms of education are divided into academic education and non-academic education. According to the education law and other laws and regulations and the relevant provisions of the state, academic education includes the following forms: primary school, junior high school, senior high school, junior college education, undergraduate education, graduate education and so on.