Determine the wavelength of light emitted or absorbed by a hydrogen atom when an electron transitions from n=9 to n=7. Give your answer in units of nm.
I keep getting 113 nm, but the system is telling me it’s weong..
Chemistry hw problem help!?
2017-10-31 9:01 pm
回答 (2)
2017-10-31 9:29 pm
Rydberg equation :
1/λ = (1.097 × 10⁷) × [(1/n₁²) - (1/n₂²)] /m
When an electron transits from n₁ = 9 to n₂ = 7 :
1/λ = (1.097 × 10⁷) × [(1/9²) - (1/7²)] /m
λ = 1 / {(1.097 × 10⁷) × [(1/81) - (1/49)]} m
λ = -1.13 × 10⁻⁵ m
λ = -11300 × 10⁻⁹ m
λ = -11300 nm
(The negative sign indicates that light is emitted.)
Wavelength of the light emitted = 11300 nm
1/λ = (1.097 × 10⁷) × [(1/n₁²) - (1/n₂²)] /m
When an electron transits from n₁ = 9 to n₂ = 7 :
1/λ = (1.097 × 10⁷) × [(1/9²) - (1/7²)] /m
λ = 1 / {(1.097 × 10⁷) × [(1/81) - (1/49)]} m
λ = -1.13 × 10⁻⁵ m
λ = -11300 × 10⁻⁹ m
λ = -11300 nm
(The negative sign indicates that light is emitted.)
Wavelength of the light emitted = 11300 nm
2017-10-31 9:24 pm
I can't see your work but.... from the rydberg equation
.. 1/L = RH * (1/n2² - 1/n1²)
where
.. L = wavelength
.. RH = rydberg constant for hydrogen = 1.097x10^7 / m
.. n2 and n1 = those numbers 9 and 7.. the principle quantum # of the orbital
because we go from n=9 to n=7
.. 1/L = (1.097x10^7 / m) * (1/9² - 1/7²)
.. L = -1.13x10^-5 m... (the - sign means light was emitted.. we can drop that)
to convert to nm.. since 1m = 10^9 nm
.. L = 1.13x10^-5m * (10^9 nm / 1m) = 11300nm
.. 1/L = RH * (1/n2² - 1/n1²)
where
.. L = wavelength
.. RH = rydberg constant for hydrogen = 1.097x10^7 / m
.. n2 and n1 = those numbers 9 and 7.. the principle quantum # of the orbital
because we go from n=9 to n=7
.. 1/L = (1.097x10^7 / m) * (1/9² - 1/7²)
.. L = -1.13x10^-5 m... (the - sign means light was emitted.. we can drop that)
to convert to nm.. since 1m = 10^9 nm
.. L = 1.13x10^-5m * (10^9 nm / 1m) = 11300nm
收錄日期: 2021-04-18 17:58:25
原文連結 [永久失效]:
https://answers.yahoo.com/question/index?qid=20171031130117AAd0zKW