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A water sample contains Ca(HCO3)2=32.4 mg/l, Mg(HCO3)2=29.2mg/l, CaSO4=13.6 mg/l. Calculate the temporary,permanent and total hardness of water sample
3-ethyl-4-methylhexa-1,3-diene undergoes a combustion reaction. For this reaction, the following
concentrations were used: [O2] = 0.06 M, [CO2] = 0.09 M and [H2O] = 0.10 M. Determine the
concentration (in mol/L) used of 3-ethyl-4-methylhexa-1,3-diene if the following thermodynamic
parameters were determined for the reaction at 25 °C: ΔH = -763.02 kJ/mol and ΔS = -2542.01 J/K
mol.
Calculate the entropy change in J/k/mol for the conversion of one mole of liquid water to vapour at 100 degrees centigrade . If the heat of vapourisation of water is 2260.87J
What is stoichiometry
6. Calculate electromotive force of a galvanic element consisting of two silver
electrodes immersed in a solution of silver nitrate with active concentration of silver
ions 0.1 mol/1 and 0.01 mol/1, T=298 K.
A. E.M.F. = 0,049 V
B. E.M.F. = 0,059 V
C. E.M.F. = 0,069 V
6.25 moles nitrogen contains how many antoms of nitrogen?
Calculate the ratio of ionized and non-ionized forms of the drug amidopirin in the stomach (pH = 2.06) and the intestine (pH = 8.06) if its pK = 5.06. Where will the drug be absorbed: in the stomach and/ or intestines?
You are to develop a computer program (in MATLAB or any computer programming code) on fuel combustion. Your program should balance the combustion equation of any hydrocarbon fuel (CnHy) as listed in Table A-25 for 100% or higher amount of moist air. Assume moist air is available at 25 C, 1 atm, and a relative humidity value that you choose. Assume complete combustion. Your program output should include: (work in SI units)
• Complete combustion equation when fuel type and percent moist air are given.
• Air fuel ratio on a mass basis and on a mole basis, water dew point temperature (total products pressure is 1 atm).
• Heat transfer calculations when reactants (1 atm, 25 C, and relative humidity), and products pressure (1 atm) and product temperature are given.
a) Run your source code for a hydrocarbon of your choice as listed in Table A-25 at 25 C to develop the following: (You need to show complete program formulation and prove that your programming code is working by showing sample formulations/calculations for at least one point. Attach a copy of your code and complete set of data to show that your program is working correctly. Note that your coding will require best-fit data for molar enthalpy values of CO2, H2O, O2, and N2 as a function of temperature from 298 K to 2000 K temperature range. Use the enthalpy data in Table 23 to get the best fit in 2nd or higher degree polynomial forms. Check and prove the goodness of your curve fits.)
1) For a range of % moist air (at a fixed relative humidity value set by you) from 100% to 200% (increments of 20%) tabulate and plot: AF ratio (mass/mole basis), and the dew point temperature versus the % air. Comment.
2) For 150% moist air at 1 atm, 25 C, and relative humidity used in part (a1) above, tabulate and plot the heat transfer release in kJ per kmole of hydrocarbon versus product temperature. Vary the product temperature from 298 K (assume water in vapor form for 25 C point for heat transfer calculations) to 2000 K. Consider 298 K, 500 K, 1000 K, 1500 k, and 2000 K points. Comment.
b) The combustion requirements of the boiler of a steam power plant using natural gas (80% methane (CH4) and 20% ethane (C2H6) on a mole basis at 25 C) are to be determined at partial/full load conditions of Wnet = 50, 75, 100 MW (full load is 100 MW). The plant overall thermal efficiencies are 36%, 38%, and 40% for each load, respectively, and the boiler efficiency is fixed for all loads at 90%. Using your generated computer code, determine the following natural gas and moist-air flow requirements as a function of the load: (clearly specify your % moist-air and the product or exhaust gas temperature for the calculations below when using your programming code): (show one point sample calculations and formulations)
1) Tabulate and plot natural gas and moist-air mole flow rates in kmoles/s vs load.
2) Tabulate and plot natural gas and moist-air mass flow rates in kg/s vs load.
Calculate the amount of carbon dioxide (CO2) that this plant dumps into the atmosphere per year (in kg/year) if this plant is run for 2000 hours, 2000 hours, and 4000 hours per year at 50, 75, and 100 MW loads, respectively.
Explain how different quantum numbers related to each other
The reaction between barium chloride and sodium carbonate gave a white precipitate which was filtered and dried. A total of 25.00 mL of 0.300 M HCl was added to 0.250 g of the resulting white precipitate with resultant fizzing and dissolution of the sample. After the reaction, 24.80 mL of 0.200 M NaOH was required too back-titrate the excess HCl. Determine the molar mass of the white precipitate. How would you confirm its identity?
