Gunpowder might have been invented by China, but it was copied and refined by the Arabs.

The Muslim world acquired the gunpowder formula some time after 1240, but before 1280, by which time Hasan al-Rammah had written, in Arabic, recipes for gunpowder, instructions for the purification of saltpeter, and descriptions of gunpowder incendiaries. Gunpowder arrived in the Middle East, possibly through India, from China.

https://en.wikipedia.org/wiki/History_of_gunpowder#Spread_th...