同学们,我们伟大的先人,在化学远未形成科学前的古代,就创造和积累了丰富的化学工艺知识。这些珍贵的知识是世界科技的宝藏,为近代化学的诞生奠定了坚实的基础,促进了化学科学的发生和发展。黑火药是我国古代科技四大发明之一,它是我国劳动人民在1千多年前的杰出发明,在化学史上占有重要的地位。最早的火药出自炼丹家之手,后为军事家所利用,得到发展和改进,于是先后出现了燃烧性火药和爆炸性火 Students, our great forerunners, have created and accumulated a wealth of knowledge of chemical processes in ancient times before chemistry was formed. These precious knowledge is the treasures of the world's science and technology, laid a solid foundation for the birth of modern chemistry and promoted the occurrence and development of chemical science. Black powder is one of the four major inventions of ancient Chinese science and technology. It is an outstanding invention of our working people over 1,000 years ago and occupies an important position in the history of chemistry. The earliest gunpowder came from the hands of alchemists and later used by military strategists to develop and improve. As a result, flammable explosives and explosive fires appeared