Mass and energy test 2 formula sheets

Mass and energy test 2 formula sheets - -use oxygen in...

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Chapter 4 hints/formulas -ALWAYS ATTEMPT A PIC AND LABELING -If there is an equation will often use to find mol ratios and/or theoretical amounts -Look for materials that have fewest places to help find unknowns -For purge/recycle or complicated processes may help to analyze a small part of system and then overall -recycle and purge will have same compostion -Bypass(branches off after too much is produced) -If there is a reactor total mols in will not equal total mols out -Often use overall atom balance (using balanced eq) can’t use mol balance if reacted -With just a reactor use the equations, find as many amounts as possible using diagram then make (often can find one compound to use in bal eq for others -variables X,Y, Z for the unknown and use equation and found value to find them -selectivity=mol desired/mol undesired Wet and dry basis: To find volumetric flow rate of air-wet basis: 1) Find flow rate of one of the compounds -Total gas(partial composition) 2) Find mols of air
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Unformatted text preview: -use oxygen in equation with compound then use 1/21 (oxygen in composition of air) 3)Use PV=nRT to find volumetric flow rate Dry basis : (combustion with excess O2) with unknown methane Basis-100mol dry 1)make percents into mols using basis and find water by using both eq 2)Find mols of methane fed(using 2 balanced eq) 3)Find actual O2 by adding amount from each compounded (ie o2 +CO2 + CO/2 + H2O/2) 4)Excess is Actual-Theor/theor Extent of reaction: n i = n io + υЄ (after=before + coeff. * extent f reaction ) Chapter 5 hints / formulas IDEAL: PV=nRT (can replace v & n for flow) can become ρ=g/v=((MW)*P)/(RT) Dalton’s Law: M total RT/ V = M A RT/ V + M B RT/ V + etc P total =P A +P B CAN USE z (corrective factor) when pressure or something ends up odd (near 1 means it doesn’t matter) will always go near T (find T R = T/T C and P R =P/ P C to find z or V(ideal)= P C V( hat )/(R T C ) to find V( hat ) use ideal pressure/temp (standard)...
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This note was uploaded on 04/06/2008 for the course CHE 2114 taught by Professor Pldurrill during the Spring '08 term at Virginia Tech.

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