Water Quality Concept Check L10 Flashcards
The units of a rate constant depend on the order of the reaction. (True/False)
True
A negative reaction rate term (-R) means that the chemical is being consumed/generated in the reaction.
Consumed
A conservative substance undergoes reaction. (True/False)
False
Theta, called the ____________ describes the average time fluids spend in a reactor
Hydraulic resonance time
The PFR model may be applied to natural systems such as rivers as well as engineered systems.
True
A spike of contaminant moves through a CSTR/PFR as a plug, not mixing with the fluid in front of or behind of it.
PFR
Reaction kinetics describe the rate at which a reaction occurs (true/false)
True
As in a CSTR, the pollutant concentration in a pfr is always homogenous throughout the reactor. (True/false)
False
What is the overall order of the reaction described in the following rate law? R=k[C6H6][NO3-]2
Third order
Oxygen demand is
The amount of oxygen consumed by biota or reacted with chemicals
What is the max amount of oxygen in clean water and why?
9 mg/l because of Henry’s law
How does temperature affect DO?
Causes DO saturation level to decrease
How dues salinity affect DO?
Causes DO saturation level to decrease
How does elevation affect DO?
The partial pressure of oxygen decreases as elevation increases, so the DO saturation level decreases
How does turbulence affect DO?
A turbulent stream will replenish DO quickly while a slow, sluggish stream will replenish DO slowly
