The laboratory will report the nitrate concentration as milligrams per liter (mg/L) or as parts per million (ppm) (1 mg/L = 1 ppm).
Most laboratories report nitrate as nitrate-nitrogen (NO3-N), which is the amount of nitrogen in the nitrate form. Some labs may report total nitrate (NO3-).
For your understanding, you can compare both as:
10 mg/L nitrate-nitrogen (NO3-N) = 44.3 mg/L nitrate
(NO3-) in drinking water.
The drinking water standard for nitrate is 10 mg/L as N (i.e., drinking waters should not...
The maximum allowed nitrite (NO2-) in drinking water is listed as 1 mg/L; for nitrate (NO3-) it is 10 mg/L. The standard half-cell potential for the nitrate <-> nitrite reaction is Eo = 0.881 V. What is the pE of a water body whose pH is 5.4 that is just at the limits of allowed nitrite and nitrate?
1. Chloroform (CHCl3) has a Drinking Water standard concentration of 0.10 mg/L . a. What is this concentration expressed as parts per million (ppm)? b. Typical consumption Risk Analysis assumes the average human drinks 2.2 L/day for 70 years. How many grams of CHCl3 would the average human consume during a lifetime at the Drinking Water standard concentration? 2. The Air Quality Standard for sulfur dioxide (SO2) is 0.04 ppm. Express this as mg/m3 at 1 atm and 25oC.
2) The EPA has determined that the maximum safe level of nitrate ion in water is 10 ppm. Suppose a sample of tap water was determined to have a nitrate ion concentration of 95 ppb. Assume the density of water is 1.00 g/mL a) What is the concentration of nitrate ion in units of ppm? Is it safe to drink? b) What is the concentration of nitrate ion in units of mg/ml? c) What mass of nitrate ion is in...
Chloroform (CHCI3) has a Drinking Water standard concentration of 0.10 mg/L What is this concentration expressed as parts per million (ppm)? Typical consumption Risk Analysis L/day for 70 years. How many grams of CHCI3 would the average human 1. a. b. assumes the average human drinks 2.2 during a lifetime at the Drinking Water standard concentration? consume Find the Volume of 1 mole of an ideal gas at 1.2 atm and 80°C 2. The Air Quality Standard for sulfur dioxide...
The drinking water standard for tetrachloroethylene is 0.005 mg/L. The potency factor for tetrachloroethylene is 5.1*10^-2(mg/kg-day)-1. What lifetime risk would this pose? Assume 30 year exposure for 350 days per year
Q.3 The drinking water standard for 2,3,7,8-TCDD (dioxin) is 3×10-8 mg/L. Using EPA exposure factors for residential consumption, what lifetime risk would this pose? Note that the potency factor of dioxin is 1.56×105 mg/kg-d.
20/27OBLEM: Suppose drinking water contains 1 mg/l of toluene and 0.01 mg/l of tetrachloroethylene (C2C4). A 70 kg adult drinks 2 t/day of this water for 10 years. a) Assess HR and evaluate HR. Was this a safe level of exposure? b) C2C4 is a carcinogen. What would be the carcinogenic risk faced by a person drinking it. Would it be less than 106 (goal)? RfDtoluene 0.2 mg/kg.day RfDc:ci 0.0 mg/kg.day PFc.c 5.1 x 10-2 (mg/kg-day) 20/27OBLEM: Suppose drinking water...
Nitrate cant excede 94,3 mg/l methemoglobinemia. Three rural wells were sampled and the report reads th concentrations as the following: Well ID Nitrate (in mg-N/L) #1 0.01 #2 1.3 #3 20 a) Convert well water readings to mg-NO3/L. b) Does any of the wells exceed the regulatory limit?
1. The drinking water standard for tetrachloroethylene is 0.005 mg/L, The potency factor for tetrachloroethylene is 5.1*10^-2 (mg/kg-day)^-1. What lifetime risk would this pose? Assume 30 year exposure for 350 days per year. 2. •Suppose a 70-kg man is exposed to 0.1 mg/m3 o etrachloroethylene in the air at his workplace. If he inhales 1m3/hr, 8 hours per day, 5 days per week, 50 weeks per year, for 30 years, and if tetrachloroethylene has an absorption factor of 90 percent...
How would you express the concentration level of drinking water 0.002 mg/L in ppm and ppb?