Question

The energy difference between the 5d and 6s sublevels in gold accounts for its color. Assuming this energy difference is about 2.7 eV (electron volt; 1 eV = 1.602 x 10⁻¹⁹ J), explain why gold has a warm yellow color.

Answer 1

Answer:

$\lambda=459.1\times 10^{-7}\ m$ = 459.1 nm

This wavelength corresponds to yellow color and thus gold has warm yellow color.

Explanation:

Given that:- Energy = 2.7 eV

Energy in eV can be converted to energy in J as:

1 eV = 1.602 × 10⁻¹⁹ J

So, Energy = $2.7\times 1.602\times 10^{-19}\ J=4.33\times 10^{-19}\ J$

Considering:-

$E=\frac{h\times c}{\lambda}$

Where,  

h is Plank's constant having value $6.626\times 10^{-34}\ Js$

c is the speed of light having value $3\times 10^8\ m/s$

$\lambda$ is the wavelength of the light

So,  

$4.33\times 10^{-19}=\frac{6.626\times 10^{-34}\times 3\times 10^8}{\lambda}$

$4.33\times \:10^{26}\times \lambda=1.99\times 10^{20}$

$\lambda=459.1\times 10^{-7}\ m$ = 459.1 nm

This wavelength corresponds to yellow color and thus gold has warm yellow color.