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Identify the INCORRECT statements from the following: A. Notation _12^24 Mg represents 24 protons and 12 neutrons. B. Wavelength of a radiation of…

JEE Main 2026 — Chemistry Physical Chemistry

2026mcqmedium

Identify the INCORRECT statements from the following:

A. Notation 1224Mg{ }_{12}^{24} \mathrm{Mg}1224​Mg represents 24 protons and 12 neutrons.

B. Wavelength of a radiation of frequency 4.5×1015 s−14.5 \times 10^{15} \mathrm{~s}^{-1}4.5×1015 s−1 is 6.7×10−8 m6.7 \times 10^{-8} \mathrm{~m}6.7×10−8 m.

C. One radiation has wavelength =λ1(900 nm)=\lambda_{1}(900 \mathrm{~nm})=λ1​(900 nm) and energy =E1=\mathrm{E}_{1}=E1​. Other radiation has wavelength =λ2(300 nm)=\lambda_{2}(300 \mathrm{~nm})=λ2​(300 nm) and energy =E2.E1:E2=3:1=\mathrm{E}_{2}. \mathrm{E}_{1}: \mathrm{E}_{2}=3: 1=E2​.E1​:E2​=3:1.

D. Number of photons of light of wavelength 2000 pm that provides 1 J of energy is 1.006×10161.006 \times 10^{16}1.006×1016.

Choose the correct answer from the options given below:

Official previous-year question

Held on 23 Jan 2026 · Verified 6 Jul 2026.

Options

  1. A

    B and C Only

  2. B

    A and D Only

  3. C

    A and C Only

  4. D

    A and B Only

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