PE Chemical Exam Questions And Answers
|Latest 2025 | Guaranteed Pass.
How to find limiting reactant - Answer✔Find the stoichiometric ratio of the reactants and
compare it to the molar ratio of the same components in the feed.
Theoretical Air - Answer✔1 mole of air = 4.76 moles Oxygen
or
1 mole Nitrogen = 3.76 moles Oxygen
standard heat of reaction of an element - Answer✔zero
Hydraulic Diameter - Answer✔Dh= (4A)/P
A = cross sectional area
P = wetter perimeter perimeter
or 4 x hydraulic radius
Homogeneous Reactions - Answer✔Reactions involving only one phase
Heterogeneous Reactions - Answer✔involve reactants in two different phases
Elementary Reactions - Answer✔The rate equation corresponds to the stoichiometric equation
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Non-elementary reaction - Answer✔there is no direct correspondence between the
stoichiometric equation
and the rate expression
reaction order - Answer✔The sum of the exponents in a rate law, where each exponent
provides the reaction order with respect to its reactant.
How to solve Chemical Reactor problems - Answer✔use the integrated reactor equations in the
handbook
How to find final concentration of reactant in a variable volume reactor - Answer✔Use the
equation for CA in variable volume batch reactor. it can be used for all types of reactors.
A reaction of gas phase reactants and products means the volume is - Answer✔Variable
equimolar counter-diffusion definition - Answer✔When one substance is diffusing through
another and is being replaced by an equal amount of the other substance. The concentration
profile is linear.
Diffusion through a stagnant component is - Answer✔When the amount of the second
substance needed to replace the diffusing component is negligible.
when solving a balance with multiple reactions use - Answer✔atomic species balance
Should you use stoichiometric coefficients in atomic species balances? - Answer✔no
Single Pass Conversion - Answer✔conversion in the reactor only
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