Questions tagged [rate-equation]
The rate-equation tag has no usage guidance.
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when to use exponents, or multiply by constants in the equation of the rate involving $k$ and concentrations?
More specifically, I do not understand
rate of consuming $\ce{I}=2 k_2[\mathrm{I}]^2+2 k_3\left[\mathrm{H}_2\right][\mathrm{I}]^2$
Why is the concentration of $"\ce{I}"$ squared from $"2 \cdot k_3 \...
user146933
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Does increasing temperature increase the rate of gaseous reactions?
In chemical kinetics there is a generalised statement that the rate of reaction is dependent upon
the concentration of reactants (except for zero order/complex reactions)
temperature
catalyst
surface ...
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Is it possible to calculate the theoretical rate of reaction?
I am conducting an experiment where I will be changing concentration (0.2 mol/dm3, 0.4 mol/dm3, 0.6 mol/dm3, 0.8 mol/dm3, 1.0 mol/dm3) and seeing how that affects the rate of reaction for a reaction ...
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HCN reactor design
For my diploma work, I should design a hydrogen cyanide (HCN) producing reactor.
I found that for the BMA process, overall
$$\ce{CH4 + NH3 -> HCN + 3 H2 \quad{} \Delta{}H_r = \pu{251 kJ / mol} }$$
...
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A first order gaseous reaction - getting the rate law
There is a specific example cited in our NCERT Class 12 textbook, to find out the rate law equation for a general gaseous reaction, $$\ce{A->B + C}$$
It describes the entire procedure as shown:
...
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Is my derivation for the reaction orders of a single-step reaction valid?
Recently in my chemistry class I learned about reaction orders. For some reaction $\ce{r_1A1}+\ce{r_2A2}+\dots+\ce{r_nA_n}\rightarrow\ce{B}$, $m_1,\dots{,m_n}$ are the orders of that reaction. The ...
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Calculate IC50 from fluorescence kinetic
I have an assay in which a fluorescence signal is generated when the enzyme reaction progresses. The fluorescence signal increases until a maximum is reached. Than it keeps constant. The first 1 h ...
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Why isn't the unit of rate constant for any reaction always per second?
It is formally agreed upon that $K_{eq}=\prod_{j}a_j^{\nu_j}$ where $\nu_j$ is stoichiometric coefficient of species $j$ (negative for reactants and positive for products). This equation results in ...
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How original is my general matrix formula for rate equations?
I was dissatisfied with the method my teacher taught me to solve rate equations, where you're given experimental values for the concentrations of reactants, and the rate of reaction, which given by
$$...
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Why Michaelis Menten Assumption of equilibrium is necessary to integrate rate of ES production
I read in my textbook that the assumptions of equilibrium and of steady state used by Michaelis and Menten were simplifying assumptions intended to make the following equation one that can be ...
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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 ...
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Rate of SN1 reaction in derivative of furan and thiopene
When I was practising questions on the rate of SN1 mechanisms, I stumbled across this:
I could eliminate options B and D because they can stabilize by only cross conjugation (if I am correct) and ...
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What is the physical significance of the frequency factor in the Arrhenius equation?
As the title says, I am wondering what the physical significance of the frequency/pre-exponential factor in the Arrhenius equation. My idea of it is that:
If the units of $E_a$ are energy per molecule,...
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Which reaction to consider for overall rate
So I have a multistep reaction
\begin{align}
\ce{4 NH3 + 5 O2 &-> 4 NO + 6 H2O}\\
\ce{2 NO + O2 &-> 2 NO2}\\
\ce{3 NO2 + H2O &-> 2 HNO3 + NO}
\end{align}
If I know the initial ...
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What equation can be used to determine the mass of water evaporation over time, when cooking?
When baking, cooking or writing recipes, it would be useful to have a ballpark estimate of evaporation rates. This question asks about water, although the answer would ideally include an ...
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