Fall 2014 Quiz Prep
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Fall 2014 Quiz Prep
An excited hydrogen atom emits light with a frequency of 1.14x10^14 Hz to reach energy level for which n=4. In what principle quantum level did the electron begin?
I got n=3 but the answer is n=6. I used the different variations of the Rydberg equation and haven't been able get the right answer.
I got n=3 but the answer is n=6. I used the different variations of the Rydberg equation and haven't been able get the right answer.
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Re: Fall 2014 Quiz Prep
If you read the question carefully, you'll notice that it says the atom emits light; thus, the change in energy between the 2 principal quantum levels must be negative. Try solving the problem with this piece of information, and you'll get n=6 as your answer.
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Re: Fall 2014 Quiz Prep
I put n=4 into n-initial and solved for n-final which allowed me to get n=6. I'm wondering why this worked because the problem asked for the quantum level where the electron began.
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Re: Fall 2014 Quiz Prep
Michael Lonsway 4E wrote:I put n=4 into n-initial and solved for n-final which allowed me to get n=6. I'm wondering why this worked because the problem asked for the quantum level where the electron began.
You got the same answer cause you did +deltaE=initial-final, and the actual way is -deltaE=final-initial. Delta E is negative since the problem says the hydrogen atoms emit light, so they're losing energy. Hope that helps!
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Re: Fall 2014 Quiz Prep
I'm also having trouble with this problem and I checked the answer for this, but I don't understand where the En= -2.178 x 10^-18 J came from in the explanation?
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Re: Fall 2014 Quiz Prep
Thanks for the help! I made Delta E negative since the problem states that energy is emitted and was able to get the right answer.
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Re: Fall 2014 Quiz Prep
A problem asks for the energy of a photon emitted with a wavelength of 5.50x10^2. I multiplied it by plank's constant and got the answer. However, I don't understand why that is if the original equations is E= h x frequency, not wavelength.
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Re: Fall 2014 Quiz Prep
In the Rydberg Equation, does n1 refer to the higher energy level or the lower energy level?
Re: Fall 2014 Quiz Prep
Is number 5 on Quiz 2014 a limiting reactant problem? And also do we have to do/turn in all three of the self-quizes or do we just turn in one? Please help
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Re: Fall 2014 Quiz Prep
Wang_Pong_Chan_1L wrote:In the Rydberg Equation, does n1 refer to the higher energy level or the lower energy level?
n1 refers to the initial energy level. Whether it is the higher or lower one depends on the problem.
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Re: Fall 2014 Quiz Prep
Rosalva_Mejia_41 wrote:A problem asks for the energy of a photon emitted with a wavelength of 5.50x10^2. I multiplied it by plank's constant and got the answer. However, I don't understand why that is if the original equations is E= h x frequency, not wavelength.
Hi! I'm not understand how you got the answer just by multiplying it by planck's constant because doing that produced 3.64 x 10^-31 which is incorrect.
For this problem you need both E=h x frequency and c= lambda x frequency. Since you're given wavelength, you need to manipulate c= lambda x frequency and plug it into E=h x frequency.
Hope that helps!!
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Re: Fall 2014 Quiz Prep
Yea that's what originally did but the workbook had a different answer. Probably a mistake. Thank you.
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