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Based on the equation: ΔE = −2.0 × 10^−18 J (1/n2^2 − 1/n1^2) what is the wavelength of the light that must be absorbed to excite hydrogen electron from level n = 1 to level n = 2 ? (h = 6.625 × 10^−34 Js, C = 3 × 10^8 ms^−1)

1. 1.325 × 10^−7 m
2. 1.325 × 10^−10 m
3. 2.650 × 10^−7 m
4. 5.300 × 10^−10 m

Correct answer: 1.325 × 10^−7 m

Solution

The correct option is right because it accurately calculates the energy difference between the two levels using the given equation, and then applies the relationship between energy, wavelength, and Planck's constant to find the wavelength of the absorbed light.

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