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Structure of the Atom — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceStructure of the Atom4 Marks
Question
Compare all the proposed models of an atom given in this chapter.
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Answer

Thomson
Rutherford
Bohr
  • Positively charged sphere
  • The negatively charged electrons are spread randomly all over inside the sphere
  • Positively charged = negatively charged
  • The net charge in the atom is zero.
  • Positively charged nucleus in the centre carrying the entire mass
  • The negatively charged electrons revolve in a well defined path
  • The size of atom is very large as compared to nucleus.
  • Positively charged nucleus in the centre
  • The negatively charged electrons revolving around do not radiate energy.
  • Orbits are labelled as K, L, M, N or n = 1, 2, 3, 4

Thomson:

Rutherford:

Bohr:

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