The energy of a single photon is 2.441 × 10⁻²⁰ J. What is the energy of one mole of these photons, in kilojoules?

• A. 2.441 kJ
• B. 2441 kJ
• C. 24.41 kJ
• D. 147 kJ

Answer: (D)

Verified step by step guidance

1. Understand that the energy of a single photon is given as 2.441 × 10⁻²⁰ J. To find the energy of one mole of photons, we need to multiply this energy by Avogadro's number, which is approximately 6.022 × 10²³ mol⁻¹.
2. Set up the calculation to find the total energy for one mole of photons: \( E_{mole} = E_{photon} \times N_A \), where \( E_{photon} = 2.441 \times 10^{-20} \) J and \( N_A = 6.022 \times 10^{23} \) mol⁻¹.
3. Perform the multiplication: \( E_{mole} = 2.441 \times 10^{-20} \times 6.022 \times 10^{23} \). This will give you the energy in joules for one mole of photons.
4. Convert the energy from joules to kilojoules by dividing the result by 1000, since 1 kJ = 1000 J.
5. Compare the calculated energy in kilojoules to the given options (2.441 kJ, 2441 kJ, 24.41 kJ, 147 kJ) to identify the correct answer.