What is the atomic theory, and who formulated it?

John Dalton, a distinguished English chemist and physicist, laid the groundwork for modern atomic theory with his pioneering work in the early 19th century. What makes Dalton's contribution noteworthy is that he was one of the first scientists to propose that matter is made up of tiny, indivisible particles called atoms. Dalton's atomic theory became a cornerstone of chemistry and offered a comprehensive explanation for various phenomena observed by scientists of his time.

His theory was based on numerous experiments and provided an explanation for the law of conservation of mass, which states that mass is neither created nor destroyed in chemical reactions. Aside from being a significant scientific figure, Dalton was also known for his work in meteorology and for being one of the first to study color blindness, which is sometimes referred to as Daltonism in his honor.

The composition of matter has intrigued humans for centuries. According to the atomic theory — which Dalton advanced — matter is composed of small, indivisible particles called atoms. These atoms are the building blocks of everything around us; from the air we breathe to the food we eat, and the materials we use.

Atoms themselves consist of a nucleus made of protons and neutrons, with electrons orbiting this nucleus. It's the arrangement and interactions between these atoms that determine the physical properties and chemical behavior of different substances. Understanding matter composition at the atomic level has enabled scientists to predict the outcomes of chemical reactions, create new materials, and explore the boundaries of what's chemically possible.

Chemical reactions are processes where substances interact to form new products, governed by the laws of chemistry that Dalton helped to frame. During these reactions, atoms are rearranged, and this rearrangement is driven by the breaking and forming of chemical bonds.

In any chemical reaction, the total mass of the reactants is equal to the total mass of the products, a principle known as the law of conservation of mass. Dalton's atomic theory plays a crucial role here by asserting that atoms are not destroyed or created during chemical reactions; they are simply reorganized. This principle allows chemists to balance chemical equations, understand reaction mechanisms and harness chemical reactions for various applications, such as energy production, pharmaceuticals, and manufacturing.