Lab Pratical II definitions

The accumulation of salts due to human activities or the natural accumulation of salts is called?

salinization. 

The typical method of comparison is known as?

Median Lethal Concentration (LC₅₀). 

In The Median Lethal Concentration (LC₅₀), “LC₅₀“ is?

the concentration of a substance that causes 50% mortality in a population of test subjects.

A location’s climate is based on?

the average weather conditions and patterns over many years.

Global climate, is based on?

the average conditions for the entire planet and is determined by the balance between the amount of energy received from the sun and the amount of energy lost in space. 

The increase in Earth’s temperature is attributed to?

the increase in greenhouse gasses in our lower atmosphere.

Greenhouse Gases include:

carbon dioxide, methane, and nitrous oxide.

The primary greenhouse gas emitted from these human activities is?

carbon dioxide, which accounts for 84% of all greenhouse gasses. 

Greenhouse gasses are emitted from?

the burning of fossil fuels, waste incineration, waste storage, and agricultural practices. 

These greenhouse gases absorb?

outgoing radiation, which in turn releases energy back onto the surface of the Earth.

This warming of the Earth’s surface is known as?

the greenhouse effect.

The United States Clean Air Act was among the first US environmental laws, with a focus on?

protecting human health. 

Passed in 1963, the Clean Air Act was repeatedly amended to?

establish national standards for air quality and to monitor and regulate air pollution.

The Clean Air Act initially focused on six major pollutants:

sulfur dioxide, nitrogen oxides, carbon monoxide, ozone, lead, and particulate matter. 

AQI stands for?

Air Quality Index. 

The AQI is calculated using amounts of?

5 major pollutants to give a measure of overall air pollution and, if necessary, warnings of associated health effects.

Drinking (potable) water ultimately comes from?

either surface or groundwater. 

According to the Environmental Protection Agency, surface water from lakes and rivers is?

the ultimate water source for 68% of public water supply users.

Ground water is?

water located underground in the pores between rocks

Ground water is a more common source in?

rural areas. 

The first step in water treatment is often?

Aeration. 

Aeration is?

adding air to water. 

Coagulation is the process by which?

dirt and other particles clump together into floc so they can be easily removed from water. 

Sedimentation is?

the process in which floc drifts down to the bottom. 

What does Filtration through a sand and pebble filter do?

removes most of the remaining impurities after coagulation and sedimentation. 

What does Disinfection using chemicals and/or ultraviolet radiation do?

kills potentially harmful microorganisms.