Jianing Jenny He
Nitrates, chlorates, and perchlorates are oxidizers and produce oxygen gas. They are used to burn reducing agents in fireworks and the Ch 3a introductory chemistry lab roman candles. At the resulting high temperatures, atoms of inorganic metal salts absorb and emit energy in the form of different colors. Here, the colors have been stripped from the picture. My digital edits have removed the colors, and there are now no clues as to the identity and composition of these fireworks. Whether it was strontium (red) or barium (green) or sodium (yellow) or potassium (purple), you will never know. Do you want to know?