
#1
Oct2712, 12:18 AM

P: 9

Calculate the wavelength of the light emitted when an electron in a onedimensional box of length 5.2nm makes a transition from the n = 7 state to the n = 6 state.
Express your answer with the appropriate units. I calculated in this way: E = n^2*h^2/8*m*a^2 E= (7^26^2)*(6.626*10^34)^2/8*(9.1*10^31)*(5.2*10^9)^2 E= 2.9*10^20 J E = hc/λ λ = 6.85*10^6 m But the answer is wrong. What is wrong with my calculation? 



#2
Oct2712, 01:08 AM

Homework
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PF Gold
P: 11,009

How do you know the answer is wrong?
It can help if you do the algebra first, then use more convenient units:$$\lambda=\frac{8(m_e c^2) L^2}{hc}\frac{1}{n_f^2n_i^2}$$ ##hc=1.240\text{eV$\mu$m}## ##m_ec^2=511\text{eV}## ##L=0.0052\text{$\mu$m}## ... give it a go. (Don't forget to check my algebra to get that equation.) 



#3
Oct2812, 01:15 AM

P: 9

I did the exercise on MasteringChemistry. It only said my answer is wrong. 


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