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(A) Schrodinger wave equation (B) Heis...

(A) Schrodinger wave equation
(B) Heisenberg uncertainty principle
(C) Millikan oil drop experiment
(D) Chadwick.s discovery of neutron
Of the scientific milestones listed above, which is the most ancient and most modern respectively ?

A

A, D

B

C, D

C

B, A

D

C, A

Text Solution

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The correct Answer is:
B
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Knowledge Check

  • Just as Bohr.s model of atom was developed on the basis of planck.s quantum theory, wave mechanical model of atom has been developed on the basis of quantum mechanics. The herat of quantum mechanism is Schrodinger wave equation which in turn is based on Heisenberg.s uncetainity principle and de broglie concept of dual nature of matter and radiation. Bohr model could explain the main lines of hydrogen or hydrogenic spectra but could not explain their fine structure. To explain this, it was suggested that each level consists of a number of sublevels, it was suggested that each level consists of a number of sublevels, the transitions between which gave rise to closely spaced lines. The numbers representing the main energy level are called Princiapl Quantum Number (n) while those representing sublevels are called Azimuthal Quantum numbers (l) and these determine the angular momentum of the electron. The orbital angular Number (m) which is just like a further split of a sublevel into finer sublevels. Lastly the electron may rotate or spin about its own axis given rise to Spin Quantum number (s) which determines the angular momentum of the electron. Total number of ndoes 4d_(xy) orbital is

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    A
    A and C
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    A and D
    C
    A and B
    D
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