1. All matter is composed of tiny, indivisible particles called atoms. This was a radical departure from the prevailing idea that matter was continuous. Dalton proposed that all matter, no matter how complex, is made up of these fundamental building blocks.
2. Atoms of a given element are identical in size, mass, and other properties. This meant that all atoms of a specific element, such as oxygen or carbon, were essentially the same.
3. Atoms of different elements have different properties. This explained why different elements have unique characteristics. For example, gold is different from silver because gold atoms have different properties than silver atoms.
4. Atoms cannot be created or destroyed in chemical reactions. This is the law of conservation of mass, which states that matter can be neither created nor destroyed in chemical reactions. Dalton's theory explained this by stating that atoms simply rearrange themselves during chemical reactions.
5. Chemical compounds are formed when atoms of different elements combine in fixed whole-number ratios. This explained the consistent composition of compounds. For example, water always contains two hydrogen atoms for every one oxygen atom.
Dalton's atomic theory, while not entirely accurate (we now know atoms can be divided into smaller particles), was a remarkable achievement. It provided a framework for understanding the nature of matter and laid the foundation for the development of modern chemistry.
