What is Pan and its effect?

What is Pan and its effect?

Peroxyacetyl nitrate (PAN) is a phytotoxic air pollutant generated by the reaction of hydrocarbons and nitrogen oxides under the action of light. This pollutant can be a restraint of plant growth in closed ecosystems as well as in the field.

What are the effects of Peroxyacetyl nitrate?

Peroxyacyl nitrates (PANs) are known to be eye irritants (lachrymators), phytotoxins, and bacterial mutagens. The most serious biological effects of PANs are of a phytotoxic nature resulting in injury to plants and vegetation.

Where do Peroxyacyl Nitrates come from?

The best known member of a class of photochemical oxidizing agents known as the peroxyacyl nitrates . The peroxyacyl nitrates are formed when ozone reacts with hydrocarbons such as those found in unburned petroleum . They are commonly found in photochemical smog .

What are the uses of Peroxyacetyl nitrate?

Peroxyacetyl nitrate, or PAN, is an oxidant that is more stable than ozone. Hence, it is more capable of long-range transport than ozone. It serves as a carrier for oxides of nitrogen (NOx) into rural regions and causes ozone formation in the global troposphere.

Which type of pollutant is PAN?

Peroxyacyl nitrates are a family of compounds which result from photochemical reactions between contaminants released to the atmosphere by combustion of organic fuels. Peroxyacetyl nitrate (PAN) is the most abundant member of this family and is responsible for serious plant injury in some polluted areas.

How do Peroxyacyl nitrates form?

Free radical reactions catalyzed by ultraviolet light from the sun oxidize unburned hydrocarbons to aldehydes, ketones, and dicarbonyl compounds, whose secondary reactions create peroxyacyl radicals, which combine with nitrogen dioxide to form peroxyacyl nitrates.

What is Pan and PBN?

A. by the action of nitrogen oxides on hydrocarbons in the presence of sunlight. by the action of carbon dioxide on hydrocarbons in the presence of sunlight. …

Who needs PAN card?

All Indian citizens having the source of income and valid proofs (as prescribed by the Income Tax Department) are eligible to apply for PAN card. Obtaining a PAN card or Permanent Account Number is mandatory for every tax payer or the person who needs to file an income tax return on behalf of self or others.

What does 4th letter of PAN indicate?

The fourth character of PAN represents the status of the PAN holder. “P” stands for Individual. “C” stands for Company. “H” stands for Hindu Undivided Family (HUF) “A” stands for Association of Persons (AOP)

What is the molecular structure of Peroxyacetyl nitrate?

The proposed reaction could yield either the accepted peroxyacetyl nitrate molecular structure or a molecular structure called acetyl pernitrate that does not include an oxygen-oxygen bond. The chemical properties of the molecule can be reconciled with either formulation.

What is the role of Peroxyacetyl nitrate in smog?

Peroxyacetyl nitrate. Peroxyacetyl nitrate is a peroxyacyl nitrate. It is a secondary pollutant present in photochemical smog. It is thermally unstable and decomposes into peroxyethanoyl radicals and nitrogen dioxide gas. It is a lachrymatory substance. Peroxyacetyl nitrate, or PAN, is an oxidant that is more stable than ozone.

How does Peroxyacetyl nitrate decompose in water?

Peroxyacetyl nitrate (PAN) decomposes in water generating hydrogen peroxide. Little is known of the mechanism of action, but oxidative stress is likely for PAN and its congeners. WHO; Environ Health Criteria 188: Nitrogen Oxides (2nd ed) (1997).

How is peroxyacetyl nitrate regenerated at high NO2 ratios?

At high NO2/NO ratios, peroxyacetyl nitrate is regenerated following each dissociation of peroxyacetyl nitrate molecule; however at NO2/NO = 3, a molecule is regenerated only one out of two dissociations; this is due to rapid reaction with NO which has a rate constant three times faster than the reaction with NO2.