1. Which postulate of Dalton's atomic theory is the result of:-
(a) Law of conservation of mass
(b) Law of definite proportions
2. What are the drawbacks of Dalton's atomic theory ?
Answers
Answer:
Answer :
Postulates of Dalton Atomic Theory :
All matters are made up of very small particles called as Atoms.
An atom cannot be further divided into smaller particles.
Atoms can neither be created nor be destroyed.
Atoms of a particular element are identical in all respects that is they have same mass, size and chemical properties.
The atoms of one element are different from other element . For example, The atoms of different elements can be distinguish from each other by their respective masses.
Atoms of different elements may combine in simple whole numbers ratio to form compound atoms of a new substance.
Thus according to Dalton's Atomic Theory atom is the smallest particle of an element which cannot be further divided and that retains all the characteristics properties of that element.
Drawbacks of Dalton's Atom Theory :
The assumption that atom is individual is no longer too. An atom can be decomposed into sub-atomic particles such as electron, proton, Neutron.
Atoms of same element may not be identical. They may have different masses. Such atoms of the same element having different masses are called Isotopes.
The atoms of different elements may be same in some aspects such atoms of different elements which have same atomic mass are called Isobars .
According to Einstein equation (E=mc²) where E is energy m is mass and C is velocity of light. Thus matter and energy are Interconvertible.
Dalton's Atomic Theory fails to explain how and why different elements combined with each other to form compound .