RankLab
Back to Questions
ChemistryMediumMCQ2014 · 19 Apr Online

Q31.The ionization energy of gaseous Na atoms is 495. 5 kJ mol−1 . The lowest possible frequency of light that ionizes a sodium atom is (h = 6.626 × 10−34 Js, NA= 6.022 × 1023 mol−1) (1) 1.24 × 1015 s−1 (2) 7.50 × 104 s−1 (3) 4.76 × 1014 s−1 (4) 3.15 × 1015 s−1

What This Question Tests

This question involves calculating the minimum frequency of light required to ionize a sodium atom, connecting ionization energy per mole to energy per atom and photon energy.

Concepts Tested

Energy of photonPlanck's constantIonization energyAvogadro's number

Formulas Used

E = hν

Ionization Energy (per atom) = Ionization Energy (per mole) / N_A

📚 NCERT Sections This Tests

12.5A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,

Physics Class 12 · Chapter 12

81% match

12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.

12.3A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What

Physics Class 12 · Chapter 12

80% match

12.3 A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?

11.6The Threshold Frequency For A Certain Metal Is 3.3 × 1014 Hz. If Light

Physics Class 12 · Chapter 11

79% match

11.6 The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.