How did the earliest idea about atoms, proposed by philosophers like Democritus, differ from the later work of scientists such as Dalton?

• A. Early ideas were based on philosophical reasoning, while later work was supported by experimental evidence.
• B. Early ideas described atoms as divisible, while later work showed atoms are indivisible.
• C. Early ideas focused on atomic mass, while later work ignored atomic mass.
• D. Early ideas included the concept of atomic orbitals, while later work rejected this.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the historical context of atomic theory. Early philosophers like Democritus proposed the idea of atoms based on philosophical reasoning without experimental evidence. They imagined atoms as indivisible particles that make up matter.
2. Step 2: Recognize that Democritus and other early thinkers lacked experimental methods, so their atomic ideas were speculative and not based on scientific data.
3. Step 3: Contrast this with John Dalton's atomic theory, which was developed in the early 19th century. Dalton's work was grounded in experimental observations, such as the laws of definite and multiple proportions.
4. Step 4: Note that Dalton proposed atoms as indivisible and indestructible particles with specific masses, providing a quantitative basis for chemical reactions, unlike the qualitative ideas of early philosophers.
5. Step 5: Summarize that the key difference is that early atomic ideas were philosophical and speculative, while Dalton's atomic theory was supported by experimental evidence and quantitative data.