lect 5 Flashcards
what is the atmosphere? where are these regions found? what are they composed of?
thin layer of gas surrounding the planet
-moderates temperature, absorbs energy which is then transferred from equatorial regions
-medium of transport of water and other important substances
-examples of regions: troposphere, stratosphere, etc
contains: gravity captured gases from space and outgassing from the crust
-major components are N2 and O2
-some minor components are CO2 and H2O
what is the hydrosphere? where are these regions found? what are they composed of?
represented by fresh water and oceans
-systems relating to and consisting of H2O (including minerals and salts found in water regions)
-97% of planet’s water is found in the oceans, and most of the remaining fresh water is trapped in ice
-sediments are generally considered part of the hydrosphere
water is involved in the hydrological cycles and other cycles. These include
a) atmospheric water (clouds, vapour, rain, snow, fog, etc)
b) surface water (rivers, lake, etc)
c) ground water
d) glaciers
what is the geosphere? where are these regions found? what are they composed of?
inorganic component of the environment
-generally called the lithosphere, consists of the upper mantle and crust of the earth (upper 50 to 100km of the crust of the earth)
-lithosphere is the part of the geosphere directly involved with environmental processes and in contact with the other compartments (interface)
-made primarily of rock (consists of rock, soil, the earth’s crust, volcanoes)
-rock is made of minerals which are naturally occurring inorganic solids with definite crystal structure and chemical composition
what is the biosphere? where are these regions found? what are they composed of?
consists of all life forms and the components necessary for their formation
-strong interactions between biotic and abiotic portions->biogeochemical cycles
-biomass crucial for life comes from biosphere
what is the anthrosphere? where are these regions found? what are they composed of?
can be referred to as the sum of human activities and processes
-a separate compartment similar to the biosphere and part of it
-environment made or modified by humans and used for their activities
-technology and its effects
-substances are removed from abiotic environment, transformed, store, used and eventually returned to the environment
-comprised of: cities, towns, fields, industry, machines, transportation
what is an ecosystem? where are these regions found? what are they composed of?
a group of organisms and their environment which are interrelated and dependent on each other
-a system including the interaction of both abiotic and biotic components within a defined area
what is a contaminant? where are these regions found? what are they composed of?
causes a change in the normal concentration of an environment but does no damage
-contamination can occur in any of the regions of the environment
-can be naturally occurring
what is a pollutant? where are these regions found? what are they composed of?
is a contaminant that causes damage (as a result of human activities)
-source: where the pollutant originates
-receptor: anything affected by the pollutant
-sink: long term depository of a pollutant (ex: limestone can be considered a sink for atmospheric sulfur acid through a chemical reaction)
what is a xenobiotic compound? where are these regions found? what are they composed of?
matter not normally part of an organism’s environment. If the compound causes damage, then it is a poison or toxic contaminant
-can be found in any region
who is this person and why is he important to environmental chemistry and beyond?
Fritz Haber
-the Haber process, also called the Haber-Bosch process
-companies around the world already produce $60 billion worth of ammonia very year, primarily as fertilizer
what is the Haber process?
what is homework example 1?
% yield= (324-51.8)/324 x 100%= 84%
what is an oxidation-reduction (redox) reaction?
-loss electrons (oxidation), or gain O
-gain electrons (reduction), or gain H
what is the summary of intermolecular forces?
-dispersion forces are the weakest of the intermolecular attractions
-dispersion forces are present in all molecules and atoms and increase with molecular weight
-polar molecules also have dipole-dipole attractive forces
-ion-dipole attractions are the strongest intermolecular attraction
-“like dissolves like”
how do hydrocarbons act in water? Are nonpolar hydrocarbons soluble in water?
generally they are not and are considered sparingly soluble
-follows the rule of “like dissolves like”
-generally, polar organics have good water solubility while nonpolar organics have poor water solubility
what is the graph of hydrocarbon solubility in water (ppm)?
- Given the solubility of toluene and phenol in water, how do we account for this difference by considering the role of IMFs
- Provide an account for the solubility difference between phenol and its conjugate base (phenolate ion)?
example: water in equilibrium with calcium carbonate
what is the solubility equilibrium?
what is molar solubility?
what is the graph of the attractions and repulsion in intermolecular forces?
what is the graph of dispersion force (london forces)?
fluctuations in the electron distribution in atoms and molecules results in a temporary dipole
what are dipole-dipole attractions?
polar molecules have a permanent dipole
-because of bond polarity and shape
-dipole moment
-as well as the always present induced dipole
the permanent dipole adds to the attractive forces between the molecules
-raising the boiling and melting points relative to nonpolar molecules of similar size and shape
what is hydrogen bonding?
what does H-bonding look like in water?
what is ion-dipole attraction?
-mixtures of ions from an ionic compound are attracted to the dipole of polar molecules
-the strength of the ion-dipole attraction is one of the main factors that determines the solubility of ionic compounds in water
what are the types of intermolecular forces?
