Answer:
1. Gunpowder was initially discovered as a lifegiving elixer for the emperor shi Huangdi, the first emperor of truly unified china. But, this actually killed him, and in most sources describing what early gunpowder was, it was described as a sulfury grey powder that if stricken by a match or flammable material would ignite
2. The first weapon designed for the use of gunpowder is the fire lance, as mentioned in the source huolongjin, and it was used since the year 950, but it was not used on mass until the siege of De'an ie during the song dynasty several centuries after
3. The Mongols facilitated the spread of gunpowder by protecting the silk road, the silk road was not a single route but multiple routes, stretching across all Mongol territory, previously the route was fairly unprotected but still protected when in Chinese territories, but when the Mongols came around the protection increased. However, this is not an excuse for the atrocities the Mongols committed on civilizations and other abuses.
Step-by-step explanation:
sources wikipedia, and books