ENV404-LECTURE 1

INTRODUCTION Chemical process shape the world we live

in-the air we breathe, the water we drink, the weather we experience

This course would cover the chemical principles which includes the natural processes occurring within and between the air, water, and soil, and explore how human activities impact on these processes, giving rise to environmental issues of global concern.

3 key environmental systems :i. the atmosphereii. Hydrosphereiii. Terrestrial environment

Topics to be covered:1.The Earth’s atmosphere

1.1 The atmosphere-composition, pressure and regions1.2 Effects of solar radiation1.3 The troposphere1.4 Calculations1.5 Reactions-photochemical and free radical

2. Stratospheric chemistry –ozone2.1 Concerns about stratospheric ozone2.2 Ozone synthesis and decomposition, catalytic cycles2.3 Quantitative calculations2.4 Anthropogenic versus natural influences2.5 “Ozone Holes”

3. Tropospheric chemistry- smog3.1 Types of smog3.2 The chemistry of photochemical smog3.3 Hydroxyl radical-initiated oxidation of hydrocarbons3.4 Emissions from the internal combustion engine

4. Tropospheric chemistry – precipitation4.1 Generation of acidity in precipitation – nitric acid and sulfuric acid4.2 Emission control technologies

 

5. Chemistry of urban and indoor atmospheres5.1 Principal atmospheric pollutants in urban areas5.2 Factors affecting indoor air quality5.3 Common indoor air contaminants

6. The chemistry of global climate6.1 Greenhouse gases and aerosol- water, carbon dioxide, methane, nitrous oxides, CFC

7. The hydrosphere7.1 Water distribution throughout the earth7.2 Physical and chemical properties of water7.3 Methods of expressing concentration of solutes in water

8. Metals and semi-metals in the hydrosphere8.1 Metals and semi-metals in the hydrosphere8.2 Environmental chemistry of calcium,copper and mercury

9. Water pollution9.1 Definition of pollution9.2 Concepts of toxicity

10. Organic biocides10.1What are biocides?10.2Mobility in soil/water systems

References :1. Environmental Chemistry – Gary

W.vanLoon and Stephen J.Duffy, 1999, Oxford

2. An Introduction to Env Chemistry – Julian E. Andrews et.al. 2009, Blackwell Publishing

What is Environmental Chemistry?

“The study of sources, reactions, transport, and fate of chemical entities in the air, water and soil environments, as well their effects on human health and the natural environment. “

Stanley Manahan

Is more complicated and difficult than ‘pure chemistry’

SULFUR OXIDE IN THE ENVIRONMENT

ACID RAIN SULFURIC ACID

SOURCE : BURNING COAL

SULFUR OXIDE

SO2 produced and released in burning coal,enters the atmosphere through the power plant stack, oxidized to H2 SO4 in the atmosphere. It will then undergo some reactions and forms acid rain which may be harmful to plants, fishes and buildings structures.

Interdisciplinary Nature of Environmental Chemistry

Environmental Chemistry can involve use of knowledge from several fields of chemistry :

Inorganic, Organic, Physical, & Analytical

Chemistry It can also involve other

areas from other scientific disciplines.

Biology and Toxicology

Societal Roles of Environmental Chemistry

Management of Industrial Emissions

Protection of Workers Health Protection of the Natural

Environment Testing and Evaluating New

Chemicals