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Identify the INCORRECT statements from the following: A. Notation ^24_12Mg represents 24 protons and 12 neutrons. B. Wavelength of a radiation of frequency 4.5 × 10^15 s^-1 is 6.7 × 10^-8 m. C. One radiation has wavelength = λ1 (900 nm) and energy = E1. Other radiation has wavelength = λ2 (300 nm) and energy = E2, E1 : E2 = 3 : 1. D. Number of photons of light of wavelength 2000 pm that provides 1 J of energy is 1.006 × 10^16. Choose the correct answer from the options given below:
- A and D only
- A and C only
- A and B only
- B and C only
Correct answer: A and C only
Solution
Option A is incorrect because the notation ^24_12Mg actually indicates 12 protons and 12 neutrons, not 24 protons. Option C is also incorrect as the energy ratio of the two wavelengths does not correspond to the stated ratio of 3:1, given that energy is inversely proportional to wavelength.
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