Question

[Ni(NH)]2+ forms a blue solution. Estimate the crystal field splitting energy (in kJ/mol) if the wavelength of maximum absorption is 455 nm. a) 2.63 x 105 b) 4.37 x 10-19 c) 263 d) 2.63 x 10-7 e) 4.37 x 10-28

Answer 1

Answer:

The correct answer is option c.

Explanation:

Wavelength absorbed by the $[Ni(NH_3)_4]^{2+}=\lambda =455nm$

Energy of the radiation = E

$E=\frac{hc}{\lambda }$

h = Planck's Constant , c= speed of the light

$E=\frac{6.626\times 10^{-34} Js\times 3\times 10^8 m/s}{4.55\times 10^{-7} m}=4.3688\times 10^{-19} J$

$1 mol = N_A=6.022\times 10^{23}$ particles

The crystal field splitting energy :

$=E\times N_A=4.3688\times 10^{-19} J\times 6.022\times 10^{23} mol^{-1}$

$=263,088.60 J/mol=263.08860 kJ/mol\approx 263 kJ/mol$