Here students can locate TS Inter 1st Year Chemistry Notes 12th Lesson Environmental Chemistry to prepare for their exam.
TS Inter 1st Year Chemistry Notes 12th Lesson Environmental Chemistry
→ The surroundings in which we live is called environment.
→ The protective blanket of gases surrounding the earth is called atmosphere.
→ Environment can be divided into four segments
- Lithosphere and
→ An unwanted chemical substance released into environment which adversely affects the environment is called a pollutant.
→ A substance which is not present in nature, but released during human activity and adversely affects the environment is called a contaminant.
→ The medium which is affected by a pollutant is called a receptor.
→ The medium which retains and interacts with the pollutant is called sink.
→ The oxygen content present in the dis¬solved state in water is called Dissolved Oxygen (DO).
→ The amount of oxygen required to oxidise organic substances present in polluted water is called Chemical Oxygen Demand (COD).
→ The amount of oxygen used by the micro-organisms present in the water for five days at 20°C is called Biochemical Oxygen Demand (BOD).
→ The permissible level of toxic pollutant in the atmosphere to which a healthy industrial worker is exposed during an 8 hour day without any adverse effect is called Threshold Limit Value (TLV).
→ The phenomenon of heating up of the sur¬face of the earth due to accumulation of CO2 and other greenhouse gases such as CH4, CFCs, O3, N2O, H2O is called Greenhouse effect or global warming.
→ Ozone in the stratosphere acts as protec¬tive layer but harmful if it is present in the troposphere.
→ Compounds containing carbon, fluorine and chlorine are called chlorofluorocarbons. They are also known as freons.
→ Freons are used as refrigerants and aerosols.
→ The active chlorine catalyses the decomposition of ozone to oxygen. This is called depletion of ozone layer.