When electromagnetic radiation of wavelength $300 \, nm$ falls on the surface of a metal,electrons are emitted with the kinetic energy of $1.68 \times 10^5 \, J \, mol^{-1}$. What is the minimum energy needed to remove an electron from the metal? $(h = 6.626 \times 10^{-34} \, J \, s, c = 3 \times 10^8 \, m \, s^{-1}, N_A = 6.022 \times 10^{23} \, mol^{-1})$

  • A
    $2.31 \times 10^6 \, J \, mol^{-1}$
  • B
    $3.84 \times 10^4 \, J \, mol^{-1}$
  • C
    $3.84 \times 10^{-19} \, J \, mol^{-1}$
  • D
    $2.31 \times 10^5 \, J \, mol^{-1}$

Explore More

Similar Questions

Find the energy of radiation having $7000 \ \mathring{A}$ and $400 \ nm$ wavelength. $\left( h = 6.62 \times 10^{-34} \ J \ s, c = 3 \times 10^8 \ m/s \right)$

Explain the reason for the formation of a spectrum.

What is an emission spectrum?

It is observed that characteristic $X$-ray spectra of elements show regularity. When frequency to the power '$n$' i.e.,$v^{n}$ of $X$-rays emitted is plotted against atomic number '$Z$',the following graph is obtained. The value of '$n$' is

Electromagnetic radiation of wavelength $242 \, nm$ is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in $kJ \, mol^{-1}$.

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo