Is the air cleaner today than it was 30 years ago?

Is the air cleaner today than it was 30 years ago?

In its first comprehensive analysis of the quality of the environment in the United States, the Environmental Protection Agency said today that the nation’s air, water and land were cleaner and better protected than they were 30 years ago but that problems remained with impure waterways, polluted air and the …

Which disaster is related to smog?

The 1952 London smog disaster December 1952 brought an episode of heavy smog to London, which lasted until March 1953. Light winds and a high moisture content created ideal conditions for smog formation.

Where is smog most common?

Cities located in basins surrounded by mountains may have smog problems because the smog is trapped in the valley and cannot be carried away by wind. Los Angeles, California, and Mexico City, Mexico, both have high smog levels partly because of this kind of landscape.

Why is smog dangerous?

Why is it harmful? When inhaled, smog irritates our airways, increasing our risk of serious heart and lung diseases. These health risks are why many cities monitor smog levels. On a high ozone-alert day, for example, your eyes and throat may burn, and you may cough and wheeze.

Is smog a natural phenomenon?

The smog is colourless, the combination of smoke and natural phenomenon. The answer of the 2nd question is “sulphur dioxide”. The sulphur dioxide reacts with the water to form the acid called sulphuric acid.

Which of the following is a secondary air pollutant?

Examples of a secondary pollutant include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight; NO2, which is formed as NO combines with oxygen in the air; and acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water.

Which of the following is an air pollutant?

These six pollutants are carbon monoxide, lead, nitrogen oxides, ground-level ozone, particle pollution (often referred to as particulate matter), and sulfur oxides.

Which of the following are likely to be present in photochemical smog?

Nitrogen oxides, such as nitrogen dioxide. Peroxyacyl nitrates.

Which is the major photochemical oxidant?

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.

Which is the major pollutants present in photochemical smog Mcq?

Which of the following pollutants is the major contributor to photochemical smog? Explanation: Ozone is the major constituent of photo-chemical smog.

Which of the following are likely to be present in photochemical smog 1 point ozone Peroxyacetyl nitrates aldehydes all of these?

Products like ozone, aldehydes, and peroxyacetyl nitrates are called as secondary pollutants. The mixture of these primary and secondary pollutants forms photochemical smog. Thus, the correct answer is option D.

Is smog a secondary pollutant?

Secondary pollutants are pollutants which form in the atmosphere. These pollutants are not emitted directly from a source (like vehicles or power plants). Photochemical smog is made up of various secondary pollutants like ozone, peroxyacyl nitrates (PANs), and nitric acid (seen in Figure 2).

Why is photochemical smog called LA smog?

Photochemical smog: This type of smog was observed in Los Angeles(1940s) and hence named as Los Angeles smog. It is formed when the air contains NO 2 and hydrocarbons and the mixture is exposed to sunlight. As the reaction take place in the presence of light to form the smog, it is called photochemical smog.

What is the difference between smoke and smog?

Smoke consists of hundreds of different chemicals, but the one we see consists of carbon, tar, oil, and ash. The smog, on the other hand, is a blend of smoke and fog which is also known as haze. When a large amount of coal is burned it creates a thick cloudy mixture of smoke and sulfur dioxide.