The Science of Firecrackers

Festival of Lights

Deepavali is the festival of lights. It is also the time of the year when children and families gather to burst firecrackers. The year 2020 has seen subdued celebrations all over India, with minimal firecrackers. I stopped indulging in firecrackers many years ago. My fascination has taken a turn towards the Science of firecrackers. This year, Deepavali has been filled with reflection and cleansing of the mind more than anything else. So, I thought it was a good time to revisit my fascination with Science and share it with you all too.

The Science

Regardless of the motivation and reasons of people who burst firecrackers and enjoy the experience, Science is fascinating. A firecracker essentially produces three distinct effects – light, sound, and heat. Let us briefly look at the Science of each.


Although every firecracker looks different, the fuel has the same basic ingredients – oxidising agents, reducing agents, colouring agents, and binding agents. Usually, metal nitrates are used as oxidising agents which form the major portion of the fuel. Charcoal and Sulphur are common reducing agents used in smaller quantities. Various metal salts in even smaller quantities are used as colouring agents. All these are held together with binding agents such as starch.


These ingredients are packaged in various ways and an appropriate fuse is added. When the fuse is lit and combustion happens, different firecrackers produce different effects. All the effects, however, are based on producing light, sound, or heat.

The combustion of fuel in the confined packed space of a firecracker produces enormous amounts of heat energy. When this enormous heat energy is released into the open air from a confined space, it results in the rapid expansion of air. This in turn produces the sound effects. The added metal salts burn with different colours, because of their distinct molecular composition. This results in colourful display.

The different metal salts responsible for colours are briefly summarised below.

  • White colour – Aluminium/Titanium/Magnesium salts
  • Green colour – Barium salts
  • Yellow colour – Sodium salts
  • Blue colour – Copper salts
  • Orange colour – Calcium salts
  • Red colour – Strontium/Lithium salts
  • Purple colour – Strontium + Copper salts mixture
The Science of Firecrackers

Safety first

The sequence of chemical reactions in each firecracker is more complex. The basic scientific principles were the topic of my rumination. Science is as fascinating as the activity itself is dangerous. Safety is of paramount importance in the presence of firecrackers. That is true for any chemical reaction.

I wish that all you readers had a fascinating Deepavali filled with illumination.

Stay curious and stay safe, until next time.

Read more Science-related articles on our blog here.


References and further reading

The Chemistry Behind Firework Colors

The Chemistry of Fireworks


Have you invested in the NumberNagar® Phonics Kit yet? It is the perfect gift for children in your family and friends’ circles. Order your kit now.

The following two tabs change content below.

Dr. Soumya Sreehari

Co-Founder and Specialist at NumberNagar®
Dr. Soumya is an Educator and Researcher with a passion for reading, writing and teaching. She holds a PhD in Chemistry (Michigan Technological University, Houghton, USA). Her experience as a student and a teacher in two countries led her to pursue a career in Education. Her core work at NumberNagar® involves quality delivery of product and services at every stage of the customer life cycle. She leads the team that makes this happen. Previously she has taught Chemistry to first year undergraduate students at Michigan Technological University. She is a voracious reader and challenges herself to read 50 books every year.

4 Replies to “The Science of Firecrackers”

  1. Loved it Dr Soumya … The simplicity in your writing and science behind crackers …. One more thing to be noted is the curiosity after lighting the cracker on the colours and the kind of sounds it produces, how high it goes and the sparks it produces. That’s an incredible experience and happiness. Simple joys of life worth reliving .

Leave a Reply

Your email address will not be published. Required fields are marked *