If the wavelength of an electromagnetic radiation is 2000 Å, what is its energy in ergs?

• 9.94 × 10^-12

• 9.94 × 10^-19

• 4.97 × 10^-12

• 4.97 × 10^-19

Which one of the following statements is correct?

• The radius (R) of a nuclide of mass number A is given by the equation R = R₀(A)^1/2 (R₀ = constant)

• ₇N¹⁵ and ₈O¹⁶ are isobars

• The end product nuclide in thorium (4n) series is ₈₃Bi²⁰⁹

• ₂₀Ca⁴⁰ has magic number of protons and magic number of neutrons

₆C¹² and ₁T³ are formed in nature due to the nuclear reaction of neutron with

• ₇N¹⁴

• ₆C¹³

• ₂He⁴

• ₃Li⁶

The atomic numbers of elements X,Y and Z are 19, 21 and 25 respectively. The number of electrons present in the M-shell of these elements follow the order

• Z > X > Y

• X > Y > Z

• Z > Y > X

• Y > Z > X

Which of the following elements has least number of electrons in its M shell ?

• K

• Mn

• Ni

• Sc

An electron is moving in Bohr's fourth orbit. Its de-Broglie wave length is λ. What is the circumference of the fourth orbit ?

• 2/λ

• 2λ

• 4λ

• 4/λ

Which of the following is correct?

• ₁H¹ and ₂He³ are isotopes

• ₆C¹⁴ and ₇N¹⁴ are isotopes

• ₁₉K³⁹ and ₂₀Ca⁴⁰ are isotones

• ₉F¹⁹ and ₁₁Na²⁴ are isodiaphers

What is the correct order of spin only magnetic moment (in BM) of Mn²⁺, Cr²⁺ and V²⁺ ?

• Mn²⁺ > V²⁺ > Cr²⁺

• V²⁺ > Cr²⁺ > Mn²⁺

• Mn²⁺ > Cr²⁺ > V²⁺

• Cr²⁺ > V²⁺ > Mn²⁺ 

109.

The energy of a photon is 3 × 10^-12 ergs. What is its wavelength in nm ?

(h = 6.62 × 10^-27 ergs ; c = 3 × 10¹⁰ cm/s)

• 662

• 1324

• 66.2

• 6.62

Which of the following is not correct ?

• Nuclei of atoms participate in nuclear reactions

• ₂₀Ca⁴⁰ and ₁₈Ar⁴⁰ are isotones

• 1 amu of mass defect is approximately equal to 931.5 MeV.

• Uranium (U²³⁸) series is known as (4n + 2) series.