Final answer:
Fireworks are composed of gunpowder and chemical compounds that include metallic elements like magnesium, aluminum, and iron, which react with oxygen to emit colorful light. Chemical reactions within fireworks result from the decomposition of barium nitrate and potassium chlorate, alongside other components.
Step-by-step explanation:
The components that propel fireworks into the air and create the patterns of colors and shapes are indeed gunpowder and various chemical compounds. The gunpowder provides the explosive force needed to launch the firework into the air and initiate the chemical reactions that produce light. These compounds undergo rapid oxidation reactions, releasing energy in the form of brightly-colored light as the atoms return to their ground energy levels after being excited. Common substances found in fireworks for coloration and effects are barium nitrate and potassium chlorate, which decompose to produce vibrant colors.
Barium nitrate's chemical formula is Ba(NO₃)₂, and potassium chlorate's is KClO₃. The decomposition of solid potassium chlorate results in the equation 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g). For barium nitrate, it decomposes as follows: 2 Ba(NO₃)₂(s) → 2 BaO(s) + 4 NO₂(g) + O₂(g). Metals such as magnesium (Mg), aluminum (Al), and iron (Fe) react with oxygen (O₂) to form their respective oxides, MgO, Al₂O₃, and Fe₂O₃ respectively. These reactions generate a significant amount of heat, contributing to the explosion and the emission of light.
Finally, the reaction of burning hydrogen with oxygen produces water, as shown in the simplified equation: 2 H₂ + O₂ → 2 H₂O.