Q: What are Dalton’s Atomic Theory Postulates?
Dalton’s Atomic Theory, proposed in the early 19th century, is one of the foundations of modern chemistry. It explains the nature of matter and how elements combine to form compounds. The key postulates are:
- Matter is made up of tiny, indivisible particles called atoms.
- Atoms of a given element are identical in mass, size, and properties, but they differ from atoms of other elements.
- Atoms cannot be created or destroyed in a chemical reaction. They only rearrange.
- Compounds are formed when atoms of two or more elements combine in fixed whole-number ratios.
- Chemical reactions are simply the rearrangement of atoms to form new substances.
Did You Know?
John Dalton was also a school teacher and had colour blindness. The condition was once called “Daltonism” after him!
❓ Frequently Asked Questions (FAQs)
Q1. Why is Dalton’s Atomic Theory important?
Dalton’s theory gave the first scientific explanation of matter at the atomic level. It formed the basis for later models like Thomson’s, Rutherford’s, and Bohr’s.
Q2. Which postulate of Dalton’s theory is not correct today?
The idea that atoms are indivisible is no longer valid. We now know atoms are made of protons, neutrons, and electrons.
Q3. How does Dalton’s Atomic Theory apply in daily life?
It explains how elements combine to form compounds like water (H₂O) or carbon dioxide (CO₂), which are essential to life.
Conclusion: Dalton’s Atomic Theory laid the foundation for modern atomic models. Although later discoveries refined some postulates, it remains a milestone in the history of chemistry.