1)

Energy of an electron is given by

   E=2.178×1018J(Z2n2)

 Wavelength of light requires to excite an electron in an hydrogen atom from level n=1 to n=2 will  be (h= 6.62 x 10-34 J s and c=3.0 x 108 ms-1)


A) 1.214×107m

B) 2.816×107m

C) 6.500×107m

D) 8.500×107m

Answer:

Option A

Explanation:

E=2.178×1018(112122)=hcλ

              2.178×1018(112122)

  =6.62×1034×3.0×108λ=1.21×107m