John Dalton's atomic theory stated that atoms are indivisible. This was disproved by the discovery of:
A. Chemical reactions
B. Isotopes
C. Subatomic particles (electrons, protons, neutrons)
D. Molecules
Answer: Option C
Solution (By JKExamLibrary)
Dalton considered atoms the ultimate, indivisible particles. The discovery of electrons (J.J. Thomson), protons (Rutherford), and neutrons (Chadwick) proved atoms are divisible and have internal structure. Isotopes showed atoms of same element can differ. However, Dalton's theory still formed the foundation of modern chemistry.
Explanation:
While Democritus proposed the philosophical concept of the atom in ancient Greece, John Dalton formulated the first scientifically based atomic theory in 1803. His theory stated that elements are composed of indivisible atoms, atoms of the same element are identical, and compounds form from atoms combining in fixed ratios.
Explanation:
Chlorofluorocarbons (CFCs) release chlorine atoms in stratosphere which catalytically destroy ozone. CO₂ causes global warming, SO₂ acid rain, N₂ is inert. Ozone hole over Antarctica is due to CFCs.
Explanation:
Metals have low ionization energies and a strong tendency to lose electrons (undergo oxidation). By losing electrons, they cause the reduction of other substances, making them excellent reducing agents. Both statements are true, and the tendency to lose electrons perfectly explains their role as reducing agents.
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