Sodium hypochlorite (NaOCl, available at a strength of 14%) is used as a disinfectant at a water treatment plant that processes 25 mgd of water. When added to water, sodium hypochlorite undergoes the reactions shown below. The facility would like to achieve an initial hypochlorite dose of 4.5 mg/L OCl- and will disinfect the water pH=7.0. The disinfection chamber will have a L:W:D ratio of 60:1:1.

Reaction #1: NaOCl-> Na+ OCl- no pKa...reaction proceeds to
completion
Reaction #2: HOCl -> H+ + OCl- pKa = 7.6

a. Based on Reaction #1, how much NaOCl (in gal/min) will be required to achieve the target dose?

answer: mole of the gas

answer: mole of the gasexplanation:

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.

d) a person who learns about the world by observing it.

explanation:

scientist are people who discover why and how things are done and made in the world.