Question

Find the maximum wavelength of the light that will excite an electron in the valence band of diamond to the conduction band. The energy gap is $5.5eV$

• A. 225 nm
• B. 315 nm
• C. 352 nm
• D. 412 nm

Answer 1

Answer: (A)

Given, $E=5.5eV=5.5\times 1.6\times 10^{-19}J$
To find ${\lambda }_{max}=$ ?
$E=\frac{hc}{\lambda }=\frac{6.6\times 10^{-34}\times 3\times 10^8}{\lambda }$
$5.5\times 1.6\times 10^{-19}=\frac{6.6\times 10^{-34}\times 3\times 10^8}{\lambda }$
$\lambda =\frac{6.6\times 10^{-34}\times 3\times 10^8}{5.5\times 1.6\times 10^{-19}}$
$\lambda =225\times 10^{-9}m$
$=225nm$