Basic Terms Flashcards
Define adsorption
Surface process that results in the accumulation of a dissolved substance at the interface of solid and solution phases
Define desorption
The release of an adsorbed substance from the surface it is held to.
Define absorption
Absorption is a process where a chemical species diffuses into the solid matrix.
Absorption is often responsible for the retention of organic compounds by SOM.
Define metal speciation
Speciation of metals refers to the diff chem forms that a metal can exist as within a particular environment. These diff forms have varying levels of toxicity, mobility, bioavailibility. Speciation determines best approach to remove contaminants.
What is a redox reaction?
An oxidation-reduction is a reaction where the oxidation number of a molecule, atom, or ion changes by gaining or losing an electrion.
When something gets oxidized, another agent gains those electrons, acting as the oxidizing agent, and gets reduced in the process. When a substance gets reduced, it gains electrons from something that gave them up, the reducing agent, which in the process gets oxidized.
What is oxidation?
A substance changes because of the loss of oxygen or reduction in oxidation numbers. These subtances are electron donors. Also act as reducing agents and cause another substance to be reduced.
Define chemical speciation
Different forms or species of an element or compound present in different environmental conditions. It is used to understand toxicity, bioavailibility, enviro fate, and transport.
Define thermodynamics
Relationship between heat, temperature, and work in relation to energy, entropy, and physical properties of matter. How energy behaves, changes, moves ect.
Mole
Elementary entities measured by n. An elementary entity may be an atom, a molecule, an ion, an electron, any other particle or specified group of particles.
Mass vs weight
Mass of a substance is the amount of matter present in it, while weight is the force exerted by gravity on an object. The mass of a substance is constant, whereas, its weight may vary from one place to another due to change in gravity.
What is chemistry
The study of atoms and molecules. Looks at reactants and products.
Scientific Notation
Can write 232.508 as 2.32508 ×102 in scientific notation. Note that while writing it, the decimal had to be moved to the left by two places and same is the exponent (2) of 10 in the scientific notation.
Similarly, 0.00016 can be written as 1.6 × 10–4. Here, the decimal has to be moved four places to the right and (–4) is the exponent in the scientific notation.
Oxyanion
Polyatomic ions involving one or more oxygen atoms plus another nonmetal atom. Commonly have a negative charges. Carbonates, nitrites, sulfite.