What would be the concentration of formaldehyde in µg/m3 if there was 128 ppb of the gas and the air was at 1.00 atm and 26.3 oC?
What would be the concentration of formaldehyde in µg/m3 if there was 128 ppb of the...
In Downtown the average concentration of atmospheric nitrogen dioxide (NO2) during March is 10 ppb; what is the concentration in µg/m3 (assume standard temperature and pressure: 25°C, 1 atm)?
Unit conversion. (10 pts) Convert a concentration of 5.62 ´1013 molecules/cm 3 to the ppb scale. Assume 25° C and 1.0 atm total air pressure. Convert a concentration of 6.0 ´1014 molecules/cm 3 to the moles per liter (molarity) scale. Assume 27.5° C and 0.99 atm total air pressure. Convert a concentration of 36.5 ppb of ozone, O3, into the number of molecules/cm3. Assume the air mass temperature is 25.3° C and its total pressure is 1.05 atm. Convert a...
3. A river with a discharge of 10 m3/s carries a concentration of 10 ppb of benzene and discharges into a 5,000,000 m3 lake. At time zero, a plant begins discharging 1 m3/s with 20 ppb of benzene. What is the concentration of benzene leaving the lake 7 days after the plant begins discharging? The benzene decay coefficient for the lake is 0.001mg/L-day. a. 5.0 ppb b. 5.1 ppb c. 5.2 ppb d. 5.3 ppb e. 5.4 ppb f. 5.5...
There is an average concentration of ethane of 2.51 ppb in the atmosphere. If the air temperature is 21.7°C and atmospheric pressure is 0.987 atm, express this concentration in units of a) ppm b) atm c) molecules/cm3 d) μg/m3 e) Determine the total mass of ethane in the atmosphere in grams with an appropriate prefix
1) The maximum allowable concentration of lead in drinking water is 9.0 ppb. (a) Calculate the molarity of lead in a 9.0-ppb solution. What assumption did you have tomake in your calculation? (b) How many grams of lead are in a swimming pool containing 9.0 ppb lead in 60 m3 of water?
The FEMA/ATSDR study also evaluated concentrations of formaldehyde in trailers ventilated using different methods. In one group of trailers, ventilation was provided using the air conditioning system with open static vents in the bathroom. After several days, the average formaldehyde concentration was found to be 0.42 ppmv. What would be the mass (in mg) of formaldehyde vapor in a trailer with a volume of 900 m3?
By referencing what you know about the relevant chemistry, explain why the ambient formaldehyde concentration would affect ozone production.
Your house is located in a polluted city with an ambient ozone concentration of 80 ppb by mole (exceeding the NAAQS!). The air intake into your house has a flow of 1500 L/min of air, which is the same as the outflow rate. Ozone is very reactive, and will oxidize chemicals (mostly at the surfaces of your house) such as the oils on the walls or on people’s skin. At steady state, if the indoor concentration of ozone in your...
15. A typical dopant concentration in a silicon device is about 1022 m3. (A) What is the ratio of the number of silicon atoms to the number of dopant atoms at this concentration? The density of silicon is 2.33 g/cm3. (B) If a manufacturing process requires that there be less than 1 uncontrolled impurity atom for every 1000 (controlled) dopant atoms, what is the allowable impurity concentration in parts per billion (1 ppb 1 impurity atom per billion silicon atoms)?...
If a certain amount of ideal gas occupies a volume 6.4 m3 with a pressure of 6.1 atm and temperature 1.7 oC on earth, what would be its volume on another planet, where the temperature is 3.3oC and the pressure is 7.7 atm ? The answer is in unit of m3