All Questions
Tagged with rate-equation concentration
10
questions
3
votes
0
answers
61
views
Does real-world gas phase chemistry use "concentration reaction quotients" (K_c)?
As a theoretical chemist, my entire exposure to reaction quotients and equilibrium constants ($Q$ and $K$) is through thermodynamics ($\Delta G^\ominus = - RT \ln K_{eq}$ and so on).
So as I started ...
- 151
3
votes
1
answer
446
views
Concentration of products in tank reactor
I want to calculate the concentrations of all components in the outlet stream of the reaction: C$_2$H$_6$ -> C$_2$H$_4$ + H$_2$ (A -> B + C)
I have a tank reactor (isothermic and isobar): V= $...
- 1,095
1
vote
1
answer
55
views
Dependence of rate on the nature of reactants and other factors
Consider a reaction
$$\ce{aA + bB -> cC + dD}$$ whose reactants are given by A and B and the products are C and D.
The rate of this reaction is given by $$\frac{dx}{dt} = -\frac{d[\ce{A}]}{adt}= -\...
- 372
0
votes
1
answer
308
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PFR reactor: -1/r vs conversion plot
A generic reagent A is considered. The behavior equations of a CSTR reactor is the following:
$$
\tau = c_\mathrm{A,0} \intop_0^{X_\mathrm{A,final}}
\dfrac{1}{-r_\mathrm{A}} dX_\mathrm{A}
$$
where $\...
- 265
-1
votes
1
answer
49
views
How does the stoichiometric coefficient affect the time until a given percentage of the reactant is consumed (if at all)?
Problem from Serway's College Physics test bank:
The reaction $2NO_2\rightarrow2NO+O_2$ obeys the rate law:
$\large \frac{\Delta[O_2]}{\Delta t} = (1.40\times10^{-2})[NO_2]^2 \space at \space 500^\...
- 173
0
votes
0
answers
41
views
How to rewrite kinetic mass balance to get to proper SI units?
Suppose from kinetic mass balance I get the following differential equation of the molarity substances $A$,$B$, and $C$ in a reactor, with molar in- or outflow rate $\phi$, and rate constant $k$:
$$
\...
- 11
3
votes
1
answer
279
views
Calculate the concentration of the reactant from the absorbance of the product without molar absorptivity
Given the reaction $\ce{A->B}$, where the absorbance of the product $\ce{B}$ has been measured (see the table below), and the initial concentration of $\ce{A}$ is $\pu{10^{-4} M},$ calculate the ...
- 1,095
0
votes
1
answer
720
views
Calculate rate constant of second order reaction and pseudo first order reaction
The reaction A + B -> Prod follows the second order kinetics. In an experiment, you initially have ten times as much B
as A. The concentration of A varies with time according to the following data:
...
- 1,095
0
votes
1
answer
542
views
Calculate concentration of product after time passed
If I have two parallel reactions:
A --> P$1$ (k$_1$ = $0.00010$ s$^{-1}$)
A --> P$2$ (k$_2$ = $0.00050$ s$^{-1}$)
and know that the initial concentration of A is $0.0417$ M. How can I ...
- 1,095
1
vote
0
answers
232
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Determining reaction order from absorbance
A reaction is initiated in a solution which contained a dissolved component. The transmittance was measured at $\pu{240 nm}$ in a $\pu{2.54 cm}$ long cell. At $t = 0$ the transmittance was $1$. $\...
- 1,095