Salient features of Dalton’s Atomic Theory

• The matter is composed of minute particles known as atoms.
• Atoms are indivisible particles that can’t be destroyed or created through chemical reactions.
• All atoms of an element have identical chemical properties and mass whereas, atoms of different elements have different chemical properties and masses.
• Atoms combine in a ratio of small whole numbers to form compounds.

The matter is anything and everything in our surrounding. It has basic structural and fundamental units. Let us examine the concept of matter with an example. Taking a storybook into consideration and dividing its structure. The book contains many pages, each page consists of paragraphs, and each paragraph has many sentences.

Each sentence will further have many words and each word will have characters. Therefore we have divided a storybook into characters. This is exactly the same case when we take the matter into account. The matter is made up of substances which contain molecules. The molecules, in turn, are made up of groups of atoms.

Atoms in simple terms are defined as the smallest unit of matter. In ancient times the scientists wondered whether the matter could be further divided or not. Around 500 BC the idea of divisibility of matter evolved in India. A scientist named Maharishi Kanad stated that matter can be divided into smaller and smaller units. The smallest unit of matter after which further division was not possible was known as parmanu.