The purge stream is an economic loss. Discuss the effects of reducing the purge flow rate on the process. Could the purge be eliminated? If so how? if not why not?

Explain the safety concerns dealing with the use of lamps and power supplies.

A triple-effect forward-feed evaporator is used to concentrate a liquid which has marginal elevation in boiling point. The temperature of the stream to the first effect is 125°C, and the boiling point of the solution within third effect is 45°C. Find out at what temperatures the fluid boils in the Ι and ΙΙ effects. The overall heat transfer coefficients are 2250W/m2 in the Ι-effect, 1800W/m2 in the ΙΙ-effect and 1300W/m2 in the ΙΙΙ-effect respectively.

A solution of HCl is standardized by titration against 0.242 g of primary standard Na2CO3. The titration requires 35.9 mL of HCl. A solid sample weighing 0.152 g and containing sodium oxide is dissolved in water (Na2O + H2O → 2NaOH) and titrated with HCl, requiring 34.7 mL. What is the percentage of Na2O in the sample?

I have certain operating conditions (pressure and temperature) given for a distillation column. Why are these conditions used? If there is a change in the operating conditions, is there an affect on the yield?

(12) Ecology is a field that involves connections among individuals, populations, species, and communities. Using succession as a framework, explain how (A) physiological performance optima, (B) the intrinsic rate of population increase, and (C) species interactions each can contribute to the progression of species from early to late succession.

What's the difference between primary and secondary succession?

a) Primary succession involves the gradual establishment of biotic communities in lifeless areas where is no soil. Secondary succession occurs where a series of communities with different species develop in places containing soil.

b) There is no difference between the two.

c) Primary and secondary succession are two sides of the same coin since both describe ecological succession; so, they are basically the same.

d) Primary succession occurs where a series of communities with different species develop in places containing soil. Secondary succession involves the gradual establishment of biotic communities in lifeless areas where is no soil.

Give an example of a disaster that leads to primary succession and list and explain each of the steps in the succeeding phases of that succession. How does primary succession differ from secondary succession? What type of succession do we see most commonly associated with clear-cutting of forests?

Can azeotrope be described or predicted by Raoult’s model? If not, why?

A mixer is used to mix 3 different streams. Stream A is an acid solution containing HNO3 = 2% weight, H2SO4 = 57% weight. Stream B contains nitric acid solution with composition of 90% weight HNO3. Stream C is a concentrated sulfuric acid solution containing 93% weight H2SO4. The mixture of those 3 streams flown out from the mixer with a flowrate of 1000 kg/hour and composition of: HNO3 = 27% weight, H2SO4 = 60% weight. a) Draw a block diagram for the process, completed with all the known variables. b) Flowrate of stream A (kg/hour) into the mixer c) Flowrate of stream B (kg/hour) into the mixer d) Flowrate of stream C (kg/hour) into the mixer e) Composition of the mixture in %moles coming out from the mixer

A well-mixed fermenter contains cells initially at concentration x0. A sterile feed enters the fermenter with volumetric flow rate F; fermentation broth leaves at the same rate. The concentration of substrate in the feed is si. The equation for the rate of cell growth is: rx = k1 x and the equation for the rate of substrate consumption is: rs = k2 x where k1 and k2 are rate constants with dimensions T-1 , rx and rs have dimensions M L -3T -1 , and x is the concentration of cells in the fermenter.

a) Derive a differential equation for the unsteady-state mass balance of cells.

b) From this equation, what must be the relationship between F, k1, and the volume of liquid in the fermenter V at steady state?

c) Solve the differential equation to obtain an expression for cell concentration in the fermenter as a function of time.

d) Use the following data to calculate how long it takes for the cell concentration in the fermenter to reach 4.0 g l-1 : F = 2200 l h-1 V = 10,000 l x0 = 0.5 g l-1 k1 = 0.33 h-1

e) Set up a differential equation for the mass balance of substrate. Substitute the result for x from (c) to obtain a differential equation in which the only variables are substrate concentration and time. (Do you think you would be able to solve this equation algebraically?)

f) At steady state, what must be the relationship between s and x?

Do some research on a specific application of chemical atalysts that you find particularly interesting. Present a summary in your own words to the class (150 or more words), making sure your posting contains the following:

How did you learn about this application?

Why did you choose it?

What did you learn from your research?

Calculation, Chrimatrographic, and Spectral Applications Experiment:

1. Based on the listed atom economy, experimental atom economy, and “E” product given, what do these values indicate about the efficiency of a dehydration reaction? (Use correct units).

-The atom economy for the reaction was 82.37%.

- The experimental atom economy was 82.40%.

- The “E” product was 70.00