The correct chronological order is (iv), (ii), (iii), (i). Dalton first proposed indivisible atoms, Thomson introduced embedded electrons, Rutherford discovered the central nucleus and Bohr explained stable quantized circular orbits with fixed energies.
Explain and arrange the following statements in the correct chronological order to show how atomic models have evolved over time. (i) Bohr’s model proposed that electrons move in fixed orbits around the nucleus, each with a definite energy. (ii) Thomson’s model depicted the atom as a ‘plum pudding’ with electrons embedded in a sphere of positive charge. (iii) Rutherford’s model proposed that atoms have a dense central nucleus. (iv) Dalton’s model described atoms as indivisible particles.
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The correct chronological sequence is (iv), (ii), (iii), then (i). In 1808, Dalton modeled atoms as indivisible building blocks. In 1897, Thomson proposed the plum pudding model featuring embedded electrons. In 1911, Rutherford established that atoms contain a dense positive central nucleus. Finally, in 1913, Bohr proposed that electrons revolve within stable, fixed energy shells without radiating energy.
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