281.

The energies E₁ and E₂ of two radiations are 25 eV respectively. The relation between their wavelength i.e., λ₁ and λ₂ will be

• λ₁ = 2λ₂

• λ₁ = 4λ₂

• λ₁ = λ₂/2

• λ₁ = λ₂/2

If n =6, the correct sequence for filling of electrons will be

• ns → (n-1) d → ( n - 2)f → np

• ns - (n-2)f → np → (n-1)d

• ns - np → (n-1)d → (n-2)f

• ns - np → (n-1)d → (n-2)f

Which is the correct order of increasing energy of the listed orbitals in the atom of titanium?

• 3s 4s 3p 3d

• 4s 3s 3p 3d

• 3s 3p 3d 4s

• 3s 3p 3d 4s

According to the Bohr theory, which of the following transitions in the hydrogen atom will give rise to the least energetic photon?

• n= 6 to n = 1

• n = 5 to n = 4

• n= 6 to n = 5 

• n= 6 to n = 5 

A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be
(h = 6.6 x 10^-34 Js)

• 6.6 x 10^-32 m

• 6.6 x 10^-34 m

• 1 x 10^-35 m

• 1 x 10^-35 m

Maximum number of electrons in a subshell of an atom is determined by the following

• 4l + 2

•  2l +1

• 4l-2

• 4l-2

The energy absorbed by each molecule (A₂) of a substance is 4.4 x 10^-19 J and bond energy per molecule is 4.0 X 10^-19 J. The kinetic energy of the molecule per atom will be

• 2.0 x 10^-20 J 

• 2.2 x 10^-19 J

• 2.0 x 10^-19 J

• 2.0 x 10^-19 J

Which of the following is not permissible arrangement of electrons in an atom? 

• n = 4, l=0, m=0, s=-1/2

• n=5, l=3, m=0, s=+1/2

• n=3, l=2, m=-3, s= -1/2

• n=3, l=2, m=-3, s= -1/2

If uncertanity in position and momentum are equal, then uncertaninty in velocity is 

The measurment of the electron position is associated with an uncerrtanity in momentum, which equal to 1 x 10^-18 g cm s^-1.The uncertanity in electron velocity is,

(mass of an electrons is 9 x 10^-28 g) 

• 1 x 10⁸

• 1  x 10⁶ cm s^-1

•  1 x 10⁵ cm s^-1

•  1 x 10⁵ cm s^-1