Ozone Formation by UV Light

3O2 → 2O3

개요

Ultraviolet radiation (wavelength < 240 nm) splits O₂ molecules in the stratosphere. The resulting oxygen atoms combine with intact O₂ to form ozone (O₃). This Chapman cycle creates the ozone layer at 15–35 km altitude, which absorbs 97–99% of UV-B and UV-C radiation that would otherwise damage DNA.

참여 물질

역할 물질 계수 상태
생성물 Ozone O₃ 2 (g)

일상 속 예시

The ozone layer protects life on Earth from harmful UV radiation. Without it, rates of skin cancer and cataracts would skyrocket.

산업적 중요성

몬트리올 의정서(1987)는 오존을 파괴하는 CFC를 금지했습니다. 오존 발생기는 수처리와 공기 정화에 사용됩니다.

성질

유형
Photochemical
가역 반응
예
에너지
흡열
ΔH
285.4 kJ/mol

관련 반응

Photochemical Smog Formation (NO₂ Photolysis) Photochromism of Spiropyran Chlorophyll Fluorescence Photodegradation of Methylene Blue by TiO₂ Photodissociation of Chlorine Gas Silver Bromide Photodecomposition Cis-Trans Isomerization of Retinal Photosynthesis Silver Chloride Photodecomposition Dye-Sensitized Solar Cell (Grätzel Cell)

Frequently Asked Questions

What is the equation for Ozone Formation by UV Light?
The balanced equation is: 3O₂ → 2O₃.
What type of reaction is Ozone Formation by UV Light?
Ozone Formation by UV Light is a photochemical reaction. It is reversible under certain conditions.
Is Ozone Formation by UV Light exothermic or endothermic?
Ozone Formation by UV Light is endothermic (absorbs energy). The enthalpy change (ΔH) is 285.4 kJ/mol.