6 after filtering a volume of unknown water rinse with a small volume of DI

6 after filtering a volume of unknown water rinse

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6) after filtering a volume of unknown water, rinse with a small volume of DI water 7) disassemble the vacuum rig by removing the clamp and funnel. proper assembly of filter rig 8) Remove the GF/F from the base and place on a clean square of aluminum foil labeled with sample ID & group number 9) Place in a drying oven at 103ºC until a constant weight is reached (1-2 hours). 10) Re-weigh using the same balance. Calculate TSS as below, normalizing for volume filtered. TSS (mg L -1 ) = (final mass - initial mass) x (1000mL/volume filtered)
pH is a measure of free hydrogen ions (really, hydronium H3O + ). The higher the concentration of H + the lower the pH. Note that pH is unitless and based on a logarithmic scale, so that the difference between pH 3.0 ( e.g. orange juice) and 7.0 ( e.g. deionized water) is 10,000x!!! Carbonated beverages (Coke) have a pH around 3.0… that’s 10,000x more acidic than freshwater and can dissolve an iron nail. 1) carefully remove the pH probe from the storage solution by first unscrewing the cap, removing the bottle, and then sliding the cap off the probe. GENTLY! DO NOT YANK THE STORAGE BOTTLE OFF THE PROBE OR YOU MAY BREAK IT! 2) open the blue vent on the side of the probe. 3) rinse the probe with DI water 4) Use the pH probe to measure the pH of two standards pH 10.0 and pH 7.0 while stirring . rinse the probe between each measurement with DI water. 5) if the standards do not match the pH reading, please inform your demonstrators. 6) if the readings match, Record pH for each depth, and rinse the probe between each measurement with DI water. 7) rinse and store the pH probe in the provided storage solution bottle. First, slide on the cap and o-ring with the threads facing down. Then insert the probe into the bottle’s solution. Bring the cap down and screw on gently. 8) replace the vent cap Thermo pH probe and standards
SALINITY is measured in parts per thousand (ppt or ‰), percent (rarely), specific gravity (mg L -1 ) and “practical salinity units” (PSU). We will use the former (ppt or ‰) to quantify the salinity of our unknown samples. Salinity exerts a strong pressure on the evolution and biodiversity of aquatic organisms and impacts ocean chemistry. To survive marine waters (>30 ppt) organisms must tolerate constant water loss from tissues, or maintain osmotic balance by storing other salts in their tissue and cells. Freshwater organisms have the opposite problem and must seek out salts and deal with eliminating excess water. 1) open the refractometer lid and rinse with deionized water. 2) wipe clean with a kimwipe 3) apply a few drops of deionized water using the disposable pipette 4) with the flat end of the refractometer facing a strong light source, look through the eyepiece 5) record the salinity from the right hand scale at the line formed between the blue and white areas 6) repeat for each depth sample 7) if the value for deionized water is positive, subtract this value from your unknown readings. if the value is negative, add this value to your unknown readings.

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• Fall '16
• Professor
• Water supply, DI, Enterococcus

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