1 it is intricately involved in just about every process on this planet in one way or another. - compos ed mere ly of two hyd ro gen atoms and o ne oxygen atom. ( po la r molecule) 1. colorless, odo rless and t ast eless 2. it dis solves nea rly eve ryt hin g 3. it exist s in thr ee forms : liq uid, soli d, ga s 4. it can absorb a large amount of heat Water as a medium on this planet also serves a role environmentally. It is very stable as temperature change because the hydrogen bonds between the water molecules themselves. When water absorbs heat, the molecules do faster but the “glue” of the hydrogen bonds slows the process. Heat is transmitted slowly though water and large bodies of water take a long time to heat up. That energy does not quickly come back out if the temperature around the water drops, either, so masses of water cool more slowly than other liquids would. Masses of water also are stable in that individual molecules that have picked up heat / motion have hard time getting free into the atmosphere, or “evaporating.” There are 2 reasons for this: (1) the heat is passed around fairly evenly and so the number of molecules going fast enough to zip free rises slowly and (2) hydrogen bonding at the water-atmosphere surface pulls molecules at the surface more tightly together (this produces the “surface tension”) and leaves less room for potential evaporating molecules to squeeze through (this explains why evaporation is a cooling process). There is also a wide range of temperature in which water is liquid; although life is tricky at extremes near freezing and boiling, it is possible as long as water remains liquid. Another fairly unique property of water is how it solidifies: if water cools, its molecules move more slowly and tend to pack more closely together. Like more substances, water gets more dense at it cools. However, when too crowded, at about 4 o C, the tightly-packed bipolar molecules begin to repel each other and slip into the arrangement which, as the temperature drops, actually pushes them further apart into kind of crystal arrangement. That’s why water is in solid form is less dense that water in its liquid form. If ice did not float, it would freeze, sink, and expose more surfaces to freeze and sink, and frozen bodies of water would be frozen solid from bottom to the surface, a very poor environment for living thins and a difficult task to thaw. In fact, ice acts as an insulator to the water underneath it. The thicker the ice, the harder it is for the water to lose heat and freeze, so ver y few deep bodies of water, ev en in the coldest climates, are totally frozen. armapua
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Water Resources and Treatment, Wastewater and Water Quality Parameters
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7/30/2019 Water Resources and Treatment, Wastewater and Water Quality Parameters
it is intricately involved in just about every process on this planet in oneway or another.
- composed merely of two hydrogen atoms and one oxygen atom. (polarmolecule)
1. colorless, odorless and tasteless2. it dissolves nearly everything3. it exists in three forms: liquid, solid, gas4. it can absorb a large amount of heat
Water as a medium on this planet also serves a role environmentally. It is very stable astemperature change because the hydrogen bonds between the water molecules themselves.When water absorbs heat, the molecules do faster but the “glue” of the hydrogen bonds slowsthe process. Heat is transmitted slowly though water and large bodies of water take a long timeto heat up. That energy does not quickly come back out if the temperature around the water
drops, either, so masses of water cool more slowly than other liquids would.
Masses of water also are stable in that individual molecules that have picked up heat /motion have hard time getting free into the atmosphere, or “evaporating.” There are 2 reasonsfor this: (1) the heat is passed around fairly evenly and so the number of molecules going fastenough to zip free rises slowly and (2) hydrogen bonding at the water-atmosphere surface pullsmolecules at the surface more tightly together (this produces the “surface tension”) and leaves
less room for potential evaporating molecules to squeeze through (this explains why evaporationis a cooling process). There is also a wide range of temperature in which water is liquid; althoughlife is tricky at extremes near freezing and boiling, it is possible as long as water remains liquid.
Another fairly unique property of water is how it solidifies: if water cools, its moleculesmove more slowly and tend to pack more closely together. Like more substances, water getsmore dense at it cools. However, when too crowded, at about 4oC, the tightly-packed bipolar
molecules begin to repel each other and slip into the arrangement which, as the temperaturedrops, actually pushes them further apart into kind of crystal arrangement. That’s why water is insolid form is less dense that water in its liquid form. If ice did not float, it would freeze, sink, andexpose more surfaces to freeze and sink, and frozen bodies of water would be frozen solid frombottom to the surface, a very poor environment for living thins and a difficult task to thaw. In
fact, ice acts as an insulator to the water underneath it. The thicker the ice, the harder it is forthe water to lose heat and freeze, so very few deep bodies of water, even in the coldestclimates, are totally frozen.
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7/30/2019 Water Resources and Treatment, Wastewater and Water Quality Parameters
This class isintended primarily for waters havingwatersheds which are inhabited and otherwiseprotected and which require only approveddisinfection in order to meet the National
Standards for Drinking Water (NSDW) of thePhilippines.
For sources of water supply that will require completetreatment (coagulation, sedimentation,filtration and disinfection) in order to meet theNSDW.
For primarycontact recreation such as bathing, swimming,
skin diving, etc. (particularly those designed fortourism purposes).
1) for propagation and
growth of fish and other aquaticresources
2) (For
boating, etc.)
3) (For
Manufacturing processes aftertreatment)
1) For agriculture, irrigation, livestock watering, etc.
2) (for
cooling, etc)3) Other inland waters, by their quality,
belongs to this classification
1) Waters suitable for the propagation,survival and harvesting of shellfish forcommercial purposes
2) Tourism zones and national marineparks and reserves established underPresidential Proclamation No. 1801;
existing laws and/or declared as suchby appropriate government agency
3) Coral reef parks and reservesdesignated by law and concernedauthorities
1) (Areas
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7/30/2019 Water Resources and Treatment, Wastewater and Water Quality Parameters
determined by measuring theamount of CO2 produced when the organic carbon in the sample isoxidized by a strong oxidizing agent and comparing with the amount
in a standard of known TOC.
the measured amount of
oxygen needed to chemically oxidize the organics present.
the measured amount of
oxygen required by acclimated microorganisms to biologicallydegrade the organic matter in the wastewater.
occurs when the discharge of waste impairs water quality or disturbs thenatural ecological balance.
This method involves the following steps:1. Manganese sulfate is introduced into the water sample made alkaline by NaOH.
MnSO4 + NaOH Mn(OH)2 + Na2SO4
2. The oxygen dissolved in the water reacts with the precipitate according to thefollowing equation.
2Mn(OH)2 + O2 2MnO(OH)2
3. The resulting precipitate is dissolved by adding sulfuric acid in the presence of KI.
2MnO(OH)2 + 4H+ + 2I- Mn2+ + I2 + 3H2O4. The evolved I2 is then titrated with standard sodium thiosulfate solution according to
the equation:
I2 + 2Na2S2O3 2NaI + Na2S4O6
A DO content of 500 mL of water sample was determined using Winkler method. During theanalysis, 200 mL of the aliquot portion of the sample was titrated with 0.025M Na2S2O3. Calculate
the DO of the water sample if the volume of thiosulfate consumed in the process was 8.3 mL.
Where : I – initial DO, mg/LF – final DO, mg/L
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7/30/2019 Water Resources and Treatment, Wastewater and Water Quality Parameters
1. Three BOD bottles were prepared with sample and dilution water as shown in thefollowing table:
1 3 297
2 1.5 298.5
3 0.75 299.25
Calculate the dilution (D) for each.
2. The BOD of a wastewater sample is estimated to be 180 mg/L at 25o
C. What volume of undiluted sample should be added to a 300 mL bottle if the initial DO is the saturation?What is the sample size and dilution factor using this volume? Assume that 2 mg/L canbe consumed in the bottle. What the BOD5 of the wastewater if the DO of the DO values
for the blank and diluted sample are 8.7 and 4.2 mg/L, respectively?
3. A test bottle containing dilution water has its DO level drop by 1.0 mg/L in a five-day
test. A 300-mL BOD bottle filled with 15 mL wateswater experiences a drop of 7.2 mg/Lin the same time period. What would be the BOD5 of the wastewater?