板书是利用简练的文字、符号和图形等将课堂教学内容概括地精练地书写在黑板上形成的板面。它是完成教学任务不可缺少的辅助手段。它能够帮助教师突出重点、突破难点、集中学生的注意力，提高学生的记忆力、理解力。目前化学教学中，最常见的板书形式是纲要式。以简明扼要的文 The blackboard is the surface of the blackboard that summarizes the contents of the classroom teaching concisely using concise words, symbols and graphics. It is an indispensable aid to complete the teaching task. It can help teachers to highlight the key points, break through the difficulties, focus students 'attention and improve students' memory and understanding. The current chemical teaching, the most common form of the board is the outline. To concise text