|Table of contents
|What is Dalton's Atomic Theory?
|Postulates of Dalton’s Atomic Theory
|Drawbacks of Dalton’s Atomic Theory of Matter
|Merits of Dalton’s Atomic Theory
What is matter made up of? What is the smallest indivisible unit of Matter?
Maharishi Kanad an ancient Indian sage, scientist and philosopher who lived in the 6th to 2nd century(actual dates not available ) first gave the atomic theory and called matter as "padarth" and atom as "parmaanu" He explained the creation and existence of universe by his Atomic before much before John Dalton gave one.
However, this theory is not entirely free of limitations. Let us now look at the drawbacks of this theory.
Example 1: Give the supporting laws for Dalton’s Atomic Theory.
John Dalton based his theory on two laws. They are explained below:
Law of Conservation of Mass:
According to the law of conservation of mass, the matter is neither created nor destroyed. In a chemical reaction, the amount of elements remains the same in starting when only reactants there and at the completion of the reaction when the product formed. We always use the “Law of conservation of mass” when we balance chemical equations.
Law of Constant Composition:
According to the law of constant composition, a pure compound will always have the same proportion of the same elements. For example, table salt with the molecular formula of NaCl holds the same proportions of the elements Na (sodium) and Cl (chlorine). This composition doesn’t depend on where the salt came from and how much salt one should have.
Example 1: Which of the following is not a postulate of Dalton’s Atomic Theory?
(a) Matter is made up of extremely small particles called atoms or molecules.
(b) Atom is the smallest particle that takes part in a chemical reaction.
(c) Atoms combine together in a simple whole-number ratio to form compound atoms.
(d) Atoms of two different elements may combine to form two or more compound atoms.
Correct Answer is Option (a)
Matter is made up of extremely small particles called atoms (not molecules).
Example 2: Which of the following laws could not be explained by Dalton’s Atomic Theory?
(a) Law of constant composition
(b) Law of multiple proportions
(c) Law of reciprocal proportions
(d) Gay Lussac’s law of gaseous volumes
Correct Answer is Option (d)
Gay Lussac’s law of gaseous volumes could not be explained by Dalton’s Atomic Theory.
|1. What is Dalton's Atomic Theory?
|2. What are the postulates of Dalton's Atomic Theory?
|3. What are the drawbacks of Dalton's Atomic Theory of Matter?
|4. What are the merits of Dalton's Atomic Theory?
|5. Can you provide a solved example related to Dalton's Atomic Theory?