Question

octyl methoxycinnamate and oxybenzone are common ingredients in sunscreen applications. These compounds work by absorbing uv b light (wavelength 280-320 nm), the UV light most associated with sunburn symptoms. What frequency range of light do these compounds absorb?

Answer 1

Answer:

0.94 PHz – 1.1 PHz

Explanation:

Case 1. 280 nm

The formula relating the frequency (f) and wavelength (λ) is

fλ = c                                         Divide both sides by f.

f = c/λ

c = 2.998 × 10⁸ m·s⁻¹

λ = 280 nm = 280 × 10⁻⁹ m     Calculate f.

f = 2.998 × 10⁸/280 × 10⁻⁹

f = 1.1 × 10¹⁵ s⁻¹ = 1.1 PHz

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Case 2. 320 nm

λ = 320 nm = 320 × 10⁻⁹ m     Calculate f.

f = 2.998 × 10⁸/320 × 10⁻⁹

f = 9.4 × 10¹⁴ s⁻¹ = 0.94 × 10¹⁵ s⁻¹ = 0.94 PHz

The frequency range is 0.94 PHz to 1.1 PHz.