Which of the following ingredients are combined to prepare traditional black powder?

I. Potassium nitrate
II. Sulfur
III. Carbon in the form of charcoal

The correct answer is I, II and III.

Traditional black powder, historically known as gunpowder, is an explosive chemical mixture composed of three fundamental ingredients:
1. Potassium nitrate (KNO₃): Functions as an oxidizing agent, providing oxygen necessary for rapid combustion even in a confined space.
2. Sulfur (S): Serves as a fuel source and significantly lowers the ignition temperature required to start the chemical reaction.
3. Carbon (C) in the form of charcoal: Acts as the primary fuel source, reacting vigorously with oxygen to release expanding hot gases.

Evaluating the statements provided:
- Statement I (Potassium nitrate): Correct, it is the oxidizer component of traditional black powder.
- Statement II (Sulfur): Correct, it is an essential ingredient used to lower ignition temperature and stabilize combustion.
- Statement III (Carbon in the form of charcoal): Correct, charcoal provides the carbon fuel for the chemical reaction.

Since all three components (I, II, and III) are combined to manufacture traditional black powder, the correct choice includes all three statements.