Answer:
3.47 × 10⁻¹⁹ J
Step-by-step explanation:
A yellow line occurs at 572.8 nm in the emission spectrum of phosphorus. When an electron undergoes this process, it requires an amount of energy to produce a photon of this light. We can calculate the energy (E) using the following expression.
E = h × c/λ
where,
- h: Planck's constant (6.63 × 10⁻³⁴ J.s)
- c: speed of light (3.00 × 10⁸ m/s)
- λ: wavelength (572.8 nm = 5.728 × 10⁻⁷ m)
E = 6.63 × 10⁻³⁴ J.s × 3.00 × 10⁸ m/s/5.728 × 10⁻⁷ m
E = 3.47 × 10⁻¹⁹ J