What is photo chemical smog and where is it usually found?
What is photo chemical smog and where is it usually found?
Photochemical smog is a type of smog produced when ultraviolet light from the sun reacts with nitrogen oxides in the atmosphere. It is visible as a brown haze, and is most prominent during the morning and afternoon, especially in densely populated, warm cities.
How do you control a photo chemical smog?
Everyone can do their part to reduce smog by changing a few behaviors, such as:
- Drive less.
- Take care of cars.
- Fuel up during the cooler hours of the day—night or early morning.
- Avoid products that release high levels of VOCs.
- Avoid gas-powered yard equipment, like lawn mowers.
Which gas is present in photo chemical smog?
Among the pollutants involved in photochemical smogs are ozone, nitrogen dioxide and peroxyacyl nitrate (PAN). The nitrogen dioxide, and other oxides of nitrogen, are primary pollutants produced by dissociation in combustion reactions, and both ‘prompt’ and ‘thermal’ NOx can be involved in the reactions.
What are the chemicals in photochemical smog?
The major undesirable components of photochemical smog are nitrogen dioxide (NO2), ozone (O3), PAN (peroxyacetylnitrate), and chemical compounds that contain the –CHO group (aldehydes). PAN and aldehydes can cause eye irritation and plant damage if their concentrations are sufficiently high.
What is photo chemical reaction?
A photochemical reaction is a chemical reaction that is initiated when the molecules of a substance absorb light energy. This reaction causes the molecules to undergo a transient excited state, consequently changing their physical and chemical properties from the original molecule of the substance.
How does photochemical smog affect humans?
Health Effects It causes painful irritation of the respiratory system, reduced lung function and difficulty breathing; this is more evident while exercising or working outdoors. High levels of smog also trigger asthma attacks because the smog causes increased sensitivity to allergens, which are triggers for asthma.
What is the difference between smog and photochemical smog?
Sulfurous smog, also known as London smog, develops due to high concentration of sulfur oxides in the air. Photochemical smog is produced when sunlight reacts with oxides of nitrogen and at least one volatile organic compound (VOC) in the atmosphere.
Is photochemical smog oxidising or reducing?
Classical smog is oxidising smog whereas photochemical smog is reducing smog.
Is the major photo chemical smog?
The most commonly known photochemical oxidants are ozone, hydrogen peroxides and peroxyacetyl nitrate (PAN). These are formed under the influence of sunlight by complex photochemical reactions. The concentrations of the photochemical oxidants depend on the primary pollutants and the sunlight.
What is smog chemically?
Smog is a specific type of air pollution. Smog is made up of many chemicals including nitrogen oxides (NOx), sulphur dioxide (SOx), carbon monoxide (CO), and volatile organic compounds (VOCs), but the two main components of smog are particulate matter (PM) and ground-level ozone (O3).
What are the photochemical processes?
photochemical reaction, a chemical reaction initiated by the absorption of energy in the form of light. The consequence of molecules’ absorbing light is the creation of transient excited states whose chemical and physical properties differ greatly from the original molecules.
What are examples of photochemical reactions?
Examples of photochemical reactions
- Photosynthesis: plants use solar energy to convert carbon dioxide and water into glucose and oxygen.
- Human formation of vitamin D by exposure to sunlight.
- Bioluminescence: e.g. In fireflies, an enzyme in the abdomen catalyzes a reaction that produced light.
What is photochemical smog and how is it formed?
Photochemical smog (or just smog for short) is a term used to describe air pollution that is a result of the interaction of sunlight with certain chemicals in the atmosphere. One of the primary components of photochemical smog is ozone.
What can be done to minimize photochemical smog?
The most obvious way to minimize photochemical smog levels is to eliminate the use of fossil fuels by using non-polluting or sustainable sources of electricity, such as nuclear power, hydropower, and wind power. Put your understanding of this concept to test by answering a few MCQs. Click ‘Start Quiz’ to begin!
What are the primary and secondary pollutants of smog?
The primary pollutants include nitrogen oxides, particularly nitric oxide and nitrogen dioxide, and organic compounds of volatile nature. The major secondary pollutants consist of peroxyacetyl nitrates, tropospheric ozone, and aldehydes. The formation of photochemical smog consists of three main ingredients.
What is smog made of?
The term smog (not to be confused with photochemical smog) is commonly used to represent a near-ground haze made of a combination of smoke and fog rather than ozone, nitric acid, and organic compounds.
