Lecture 5

Question 1

what type of reactions is photosynthesis?

Answer 1

redox reaction!

Question 2

what are the 2 types of cycles?

Answer 2

1. exogenic: above ground 2. endogenic: below ground

Question 3

how do micro-organisms play into the nitrogen cycle?

Answer 3

elemental nitrogen is incorprated into chemically bound forms or fixed by biochemical processes mediated by microorganisms. They also return into into gases to the atosphere through denitrification,

Question 4

what phosphorous is bad?

Answer 4

can be extremely toic such as organophosphate inseticides and military poision nerve gases like VX.

Question 5

as frequency goes up what happens to energy?

Answer 5

also goes up

Question 6

what is a solution when you have a lot of blue-green algae?

Answer 6

cross polymner with lots of cross link with copper can absorb lots of urea.

Question 7

deine biochemical oxygen demand (BOD)

Answer 7

the amount of dissolved oxygen that must be present in water in order for microorganisms to decompose the organic matter in the water, used as a measure of the degree of pollution.

Question 8

what are the products from photosynthesis:

Answer 8

1. biomass 2. cellulose 3. oxygen 4. starch

Question 9

a very ——- amount of carbon is present in minerals, particularly (give example)

Answer 9

large/ magnesium and calciuym carbonate as CaCO3

Question 10

in the geosphere where is phosphorous held?

Answer 10

largely in poorly soluble minerals, such as hydroxyapatite a clacium salt deposits of which constitue the major reservoir of environmental phosphate.

Question 11

what compoinent of the atmosphere is nitrogen?

Answer 11

78%

Question 12

what do micro-ogranisms do in the carbon cycle?

Answer 12

degrade organic carbon from biomass, petroleum and xenobiotic sources ultimately returning it to the atmosphere as CO2.

Question 13

what are the 12 principles of green chenistry;

Answer 13

1. prevent wastes 2. use all materials 3. avoid hazarous substances 4. minimize toxicity 5. minimize auxiliary substances 6. minimize energy consumption 7. use renewables 8. minimize protecting groups 9 maximize reagent selectivity 10. degradibility of products released 11. monitor and carefully control processes 12. avoid extremes

Question 14

some of the carbon is dissolved in surface water and groundwater as what?

Answer 14

HCO3- or molecular CO2 (aq)

Question 15

is the phosphorous cycle part of the exogenic or endogenic cycle?

Answer 15

endogenic cycle.

Question 16

why is nitrogen limiting nutrient?

Answer 16

the N2 molecule is very table so that breaking it down into atoms that can be incorporated with inorganic and organical chemical forms

Question 17

for H2 + F2 –> 2 HF what species are oxidized and reduced? which is the oxidizng and reducing agents?

Answer 17

F2 is udnergoing reduction –> oxidizng agent H2 is undergoing oxidation –> reducing agent

Question 18

when there is a loss of electrons what is this called?

Answer 18

oxidation!

Question 19

whats the difference and similarities between DDT and parathion

Answer 19

they both have an aromatic ring, but DDT is persistent and can bio-accumulate. Parathion is toxic but can break down due to the bonds. Both are toxic but one can break down and one cannot

Question 20

as wavelength goes down what happens to frequency?

Answer 20

goes up!

Question 21

define environmental chemistry:

Answer 21

study of the sources of reactions, transport, effects and fate of chemical species in water/air/soil and living environments and the effects of technology theron

Question 22

what is the constant C units in?

Answer 22

velocity m/s

Question 23

what is a supercritical fluid?

Answer 23

is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist.

Question 24

what are the two chemical equations in the carbon cycle?

Answer 24

CO2 –> (CH2O)n photosynthesis CO2 –> CO2 (aq) –> HCO3- (aq)

Question 25

is the nitrogen cycle exogenic or endogenic?

Answer 25

both!

Question 26

why is the phosphorous cycle so crucial?

Answer 26

because it is a limiting nutrient in the ecosystem.

Question 27

are there any catalysts involved in photosynthesis?

Answer 27

chlorophyll!!!! There is an iron inside chloophyll that allows electron transfer

Question 28

explain the evolution of the anthrosphere:

Answer 28

1. ignore pollution- dump wastes 2. control pollutants and wastes after production 3. closed loop systems- integrate with the total environment

Question 29

when there is a gain of electron what is this called?

Answer 29

reduction

Question 30

the sulfure cycle is parth of the exogenic or endogenic cycle?

Answer 30

both!

Question 31

what happens with photosynthesis in the water?

Answer 31

algae is the predominant carbon-fixing agents in water as the consume CO2 to produce biomass, the pH of the water increases, enabling precipitation of CaCO3 and CaCO3, MgCO3

Question 32

Frequency of light is characterized as V which really means?

Answer 32

Hz or S^-1

Question 33

as pollution is concerned what are the major concerns with the sulfur cycle?

Answer 33

presence of pollutant SO2 which is a toxic gaseous air pollutant evolved in the combustion of sulfur containing fossil fuels. and H2SO4 wich happens when sulfur dioxide xoidizes in the atmosphere to produce sulfuric acid or acid rain.

Question 34

is carbon cycle exogenic or endogenic?

Answer 34

both!

Question 35

what is the haber process?

Answer 35

N2 + 3H2 2NH3 changes the timeline of history in the fertilize industry, a stable food supply in the field of agriculture and the industrial era.

Question 36

what are 3 characteristics of undesirable chemicals?

Answer 36

1. Persistence (e.g. DDT) 2. bioaccumulation 3. toxicity (e.g. parathion)

Question 37

write out the basic photosynthesis equation:

Answer 37

6CO2 + 6 H2O + Energy –> C6H12O6 + 6O2

Question 38

what is an important aspect of the carbon cycle?

Answer 38

is that it is the one by which solar energy is transferred to biological systems and ultimately to the geosphere and anthrosphere as fossil carbon and fossil fuels

Question 39

is anaerobic or aerobic a redox reaction

Answer 39

both!

Question 40

why is photosynthesis important?

Answer 40

cycles of carbon and oxygen depend highly on photosynthesis.

Question 41

define total suspended solids (TSS)

Answer 41

is the dry-weight of particles trapped by a filter. It is a water quality parameter used for example to assess the quality of wastewater after treatment in a wastewater treatment plant.

Question 42

what are supercritical liquids good at getting rid of?

Answer 42

waste!

Question 43

how does the anthrosphere play into phosphrous in the environment?

Answer 43

because we extract large quantities from phsophate minerals for fertilizer, chemicals and food additives.