The incorrect postulates of the Dalton's atomic theory are :
(A) Atoms of different elements differ in mass.
(B) Matter consists of divisible atoms.
(C) Compounds are formed when atoms of different element combine in a fixed ratio.
(D) All the atoms of given element have different properties including mass.
(E) Chemical reactions involve reorganisation of atoms.
Choose the correct answer from the options given below :
(A) Atoms of different elements differ in mass.
(B) Matter consists of divisible atoms.
(C) Compounds are formed when atoms of different element combine in a fixed ratio.
(D) All the atoms of given element have different properties including mass.
(E) Chemical reactions involve reorganisation of atoms.
Choose the correct answer from the options given below :
- (B), (D), (E) only
- (A), (B), (D) only
- (C), (D), (E) only
- (B), (D) only
The Correct Option is D
Solution and Explanation
Statement (B) is incorrect because Dalton proposed that atoms are indivisible, but later discoveries (e.g., protons, electrons, neutrons) disproved this. Statement (D) is incorrect because Dalton stated that atoms of the same element are identical in all properties, including mass. Statement (E) is correct as chemical reactions involve the reorganization of atoms but do not change their nature.
Thus, the incorrect postulates are (B) and (D) only.
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