1. What is environmental chemistry and how is it applied in environmental science?
2. State the main processes that move chemicals between the different spheres in the environment.
3. State the major types of pollutants in the environment and how these pollutants move between the
different spheres in the environment.
4. Differentiate between an atom, element, compound, molecule and ion and give an example of each.
5. Differentiate, atomic number, atomic mass, isotope and give an example of each.
6. Differentiate between major, minor and trace elements.
1. Environmental chemistry is the study of chemical processes occurring in the environment, including air, water, soil, and living organisms. It is applied in environmental science to understand how pollutants are generated, transported, transformed, and degraded in the environment.
2. The main processes that move chemicals between the different spheres in the environment include diffusion, advection, precipitation, evaporation, absorption, desorption, and chemical reactions.
3. The major types of pollutants in the environment include heavy metals, pesticides, industrial chemicals, and greenhouse gases. These pollutants move between the different spheres in the environment through processes such as atmospheric deposition, surface runoff, leaching, and bioaccumulation.
4. - Atom: The smallest unit of matter that retains the properties of an element. Example: Carbon atom.
- Element: A substance made up of only one type of atom. Example: Oxygen.
- Compound: A substance made up of two or more different elements chemically bonded together. Example: Water (H2O).
- Molecule: A group of two or more atoms bonded together. Example: Oxygen molecule (O2).
- Ion: An atom or molecule with a net electric charge due to the loss or gain of electrons. Example: Sodium ion (Na+).
5. - Atomic number: The number of protons in the nucleus of an atom. Example: Carbon has an atomic number of 6.
- Atomic mass: The total number of protons and neutrons in the nucleus of an atom. Example: Carbon-12 has an atomic mass of 12.
- Isotope: Atoms of the same element that have the same number of protons but a different number of neutrons. Example: Carbon-14.
6. - Major elements: Elements that are present in relatively high concentrations in a sample. Example: Oxygen.
- Minor elements: Elements that are present in lower concentrations compared to major elements. Example: Magnesium.
- Trace elements: Elements that are present in very small amounts in a sample but are still essential for biological processes. Example: Zinc.