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### Test 2 Q.4

Posted: Tue May 08, 2018 2:06 am
Q: A cotton ball soaked in $CaCl_{2}$ is lit on fire. The flame is a dark orange color $(\lambda =630.nm)$ . A scientist claims that the color arises from the transition of an electron from its excited state to its ground state. What is the difference in energy between these two states?

Help?? Im confused as to how we are supposed to do this since we are given the wavelength.

### Re: Test 2 Q.4

Posted: Tue May 08, 2018 1:05 pm
You can use the wavelength to determine the energy released (where an electron went from a higher energy level to a lower energy level). This energy is the difference in energy between the two states.

Hope this helps! Try to work out the problem, and if you are still having trouble I can write out the steps.

### Re: Test 2 Q.4

Posted: Wed May 09, 2018 11:36 am
I have the problem worked out, would it be possible for anyone to work out the steps? Just want to make sure I did it correctly.

### Re: Test 2 Q.4

Posted: Wed May 09, 2018 12:26 pm
You can use two equations to reach a final answer. The first equation is deltaE=hv(frequency). You can then use the equation v(frequency)=c/wavelength as a substitute for v(frequency). This will give you the combined equation of deltaE=hc/wavelength. H and C are both constants and the wavelength is given to you.