Day 1 Others Memorize Flashcards
(Nov. 2019 PBE) The distance of the Earth to
the most remote normal galaxy is calculated
to be:
2x1022m
A certain volume of a
solution of KMnO4 will oxidize sufficient
potassium tetraoxalate that requires half of
that volume using 0.201N of KOH solution
for neutralization. Determine the quantity
of KMnO4 in a liter of its solution.
b. 2.01g
key: potassium tetraoxalate
A newly graduate chemical engineer was assigned to team of
engineers in food processing plant.
B-B
Determine the BEST combination of plant and location to BEST
conserve the environment, given the following data:
a. Plant (B) in Marikina River
Key: High DO, low D
How many trucks would be needed to collect the waste twice weekly? The trucks each have a capacity of 4.5 MT and operate 5 days per week. Assume that the trucks average two loads per day at 75% capacity.
Germany – 4, US – 8
A Chemical Engineer decided to make a twist with the old Filipino song “Ako ay may Lobo”. If the child had a 500 mL balloon (5/6 of its Maximum Stretching Capacity) filled with H2 gas, at what height will the child no longer see the balloon since it has burst? Assume that the pressure decreases 1 mm for every 100 cm rise in height.
127 m
Determine the volume of carbon dioxide in cubic feet occupied by 120 lbs at a pressure of 1.5 atm.
750
Temp: 105 F
Determine the number of days it will take for one milligram of rubidium to decay to 0.6 mg.
63
half life used: 86.2 days (Rb-83)
Glutamic acid is used as one of the reagents for a standard to check the BOD test. Determine the theoretical oxygen of 150 ppm of glutamic acid.
212 ppm
The design flow and overflow rates for a settling tank are 0.044 m3 · s−1 and 20 m · day−1, respectively. Determine the surface area of this tank. Determine the length of the tank, using conventional wisdom for length- to-width ratios. Determine the tank depth, assuming a detention time of 2 hours.
190 m2, 16 m and 1.7 m
W=L/5
A power plant in a college town is burning coal on a cold, clear winter morning at 8:00 A.M. with a wind speed of 2.6 m · s−1 measured at 30 m elevation and an inversion layer with its base at a height of 697 m. The effective stack height is 30 m. Calculate the distance downwind XL at which the plume released will reach the inversion layer and begin to mix downward.
5.8 km
A town of 20,000 in Laguna generates 0.96 kg/(capita)-day of MSW. A town of the same size in the Makati City in Metro Manila generates 1.9 kg/(capita)-day of MSW.
How much MSW is generated in each town?
How many trucks would be needed to collect the waste twice weekly? The trucks each have a capacity of 4.5 MT and operate 5 days per week. Assume that the trucks average two loads per day at 75% capacity. Calculate the number and volume of MSW in tons that enter the landfill
19100 kg/d and 39000 kg/d, 4 and 8 trucks, 58 m3/d 105 m3/d
The Nairyosangha landfill located in Peshdadians serves a population of 562,400 people generating MSW at a rate of 1.89 kg · capita−1 · day. The volume of the landfill is 11,240,000 m3. At the present time, 63% of the landfill is used. The ratio of cover to compacted fill is 1.9. Determine projected life remaining for the landfill. Assume the density of the compacted waste to be 490 kg · m−3.
2.76 years
Start with volume then dimensional analysis
A landfill with a gas collection system is in operation and serves a population of 200,000. MSW is generated at a rate of 1.95 kg · (capita)−1 · day−1. Gas is produced at an annual rate of 6.2 L · kg−1 of MSW delivered to the landfill. The gas contains 55% methane. Gas recovery is 15% of that generated. The heat content of the landfill gas is approximately 17,000 kJ · m−3 (a value lower than the theoretical value because of dilution of the methane with air during recovery). The landfill company and a developer have proposed to build a subdivision in the vicinity of the landfill and pipe the methane generated to the homes to be used for heating. The homes are estimated to use an average of 110 × 106 kJ of heat energy each year. Peak usage during winter is 1.5 times the average usage. How many homes can be built in the subdivision?
7 homes
A solution of HOCl is prepared in water by adding 15 mg HOCl to a volumetric flask, and adding water to the 1-L mark. The final pH is measured to be 7.0. What are the concentrations of HOCl and OCl? What percent of the HOCl is dissociated? Assume the temperature is 250C.
[OCl-] = 6.39x10-5 M, [HOCl] =
2.22x10-4 M, 22.4%
If the normality of HCl is greater by 10% compared to KOH, estimate the normality of the HCl solution when 0.67g of (NH4)2SO4 is dissolved in water, treated with excess NaOH and the ammonia released is passed through a solution of 20mL of HCl. The excess acid solution is titrated using 15.01mL of KOH solution.
0.152 N
A solution is initially supersaturated with CO2− and Ca2+ such that the concentrations are both 3
50.0 mg · L−1. When equilibrium is ultimately reached what will be the final concentration of Ca2+?
16.7 mg · L−1
U-238 half life
4.52x10^9 years
A rock contains 0.688 mg 206Pb for every 1.000 mg
238U
present. Assuming that no lead was originally present, that all the 206Pb formed over the years has remained in the rock, and that the number of nuclides in intermediate stages of decay between 238U and 206Pb is negligible, calculate the age of the rock.
3.8×10^9 years
A sewage lagoon that has a surface area of 10 ha and a depth
of 1 m is receiving 8640 m^3 d^- of sewage containing 100 mg
T^_ of biodegradable contaminant. At steady state, the effluent from the lagoon must not exceed 20mg• L^ - of biodegradable contaminant. Assuming the lagoon is well mixed and that there are no losses or gains of water in the lagoon other than the sewage input, what biodegradation reaction rate coefficient (d^-) must be achieved for a first-order reaction?
0.35
An air jet operates at 2,500 rev/min and uses 7.89 × 10^3J of energy and exhausts 4.58 × 10^3 J for each crankshaft revolution.
Determine the quantity of gasoline fuel
consumed in one hour of operation if the heat of combustion is 4.03 × 10^7 J/liter.
29.4 L/h
Suppose that we have a stain on an oil painting that we want to remove without damaging the painting. The stain is not water-insoluble. Knowing the polarities of the following solvents, which one would we try first: benzene, isopropyl alcohol, hexane
isopropyl alcohol
There are approximately 20 amino acids in human protein.
Name 3 essential amino acids:
A
). Proline, glutamine, asparagine
B. Arginine, lysine, phenylalanine
C. Aspartic acid, glutamic acid, serine
D. Glycine, arginine, glutamic acid
B. Arginine, lysine, phenylalanine
How do two free radicals react when they encounter each other?
They unite with covalent bond formation
