Terminologies

Question 1

Osmosis

Answer 1

The movement of water from regions of higher potential (activity) to regions of lower potential (activity).

Question 2

Diffuse double layer

Answer 2

The surface of a clay particle, being negatively charged, attracts positive ions. This region of attracted positive ions in solution and the negatively charged surface of the layer is termed as diffused double layer.

Question 3

Stern layer

Answer 3

The innermost layer of double layer water, which is held very strongly by clay, is known as adsorbed water (Stern layer). Initially, attraction from the negative colloid causes some of the positive ions to form a firmly attached layer around the surface of the colloid; this layer of counter-ions is known as the Stern layer.

Question 4

Composting

Answer 4

It is a process to dispose organic matter of solid waste that has proved generally uneconomical and also resulted in metal enrichment of the system.

Question 5

Contaminant

Answer 5

Contaminants are substances that have not been intentionally added to food.

Question 6

Contamination

Answer 6

The action or state of making or being made impure by polluting or poisoning.

Question 7

Pollutant

Answer 7

A substance that pollutes something, especially water or the atmosphere.

Question 8

Persistent pollutant and persistence

Answer 8

Persistent organic pollutants are toxic chemicals that are slow to break down. When released, they stay in the environment for a long time and accumulate in the food chain and living organisms. That’s why they are also sometimes referred to as forever chemicals.

Question 9

Pollution

Answer 9

Pollution is the introduction of harmful materials into the environment.

Question 10

Residual time

Answer 10

The average time that a water molecule or particulate pollutant spends in the atmosphere. The residence time for pollutants ranges from a few weeks in the lower troposphere to several years in the upper stratosphere, before it is scavenged out by precipitation.

Question 11

Half-life

Answer 11

The time taken for the radioactivity of a specified isotope to fall to half its original value.

Question 12

Bioavailability

Answer 12

Relative bioavailability of a contaminant in soil is how much of a contaminant is absorbed from soil as compared to how much of that contaminant is absorbed from a reference exposure medium (e.g., food, water) that relates back to the toxicity value of the contaminant.

Question 13

Phytoremediation

Answer 13

The use of plants and associated soil microbes to reduce the concentrations or toxic effects of contaminants in the environment.

Question 14

Mobility

Answer 14

The ability to move or be moved freely and easily.

Question 15

Solubility

Answer 15

The new bond formation between the solute molecules and solvent molecules.

Question 16

Acid saturation

Answer 16

The number of carbon to carbon double bonds within their structure.