Rate laws, Arrhenius theory, reaction mechanisms, particle in a box, molecular orbitals and the Born-Oppenheimer approximation.
40 cards · basic cards · AI-written, checked twice. Edit anything.
- What is the rate law for a reaction?
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The relationship between the reaction rate and reactant concentrations, expressed as rate = k[A]^m[B]^n, where k is the rate constant and m, n are reaction orders- What does reaction order mean?
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The sum of the exponents in the rate law; it indicates how strongly the rate depends on concentration changes- Write the integrated rate law for a first-order reaction.
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ln[A] = -kt + ln[A]0, or equivalently ln([A]0/[A]) = kt- Write the integrated rate law for a second-order reaction.
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1/[A] = kt + 1/[A]0, or equivalently 1/[A] - 1/[A]0 = kt- What is the half-life formula for a first-order reaction?
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t(1/2) = ln(2)/k = 0.693/k; it is independent of initial concentration- What is the half-life formula for a second-order reaction?
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t(1/2) = 1/(k[A]0); it is inversely proportional to the initial concentration- What is the rate law for a zero-order reaction?
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rate = k; the concentration changes linearly with time as [A] = -kt + [A]0- What does the rate constant k represent?
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The proportionality constant in the rate law that determines reaction speed at a given temperature; its units depend on overall reaction order- What does the method of initial rates determine?
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The reaction orders and rate constant by comparing initial rates under different initial concentrations; rate law expressions are compared at each concentration level- State the Arrhenius equation.
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k = A*exp(-Ea/RT), where A is the frequency factor, Ea is activation energy, R is the gas constant, and T is absolute temperature- What is activation energy (Ea)?
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The minimum energy required for reactant molecules to form the activated complex and proceed to products; always positive- What is the frequency factor (A) in the Arrhenius equation?
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A pre-exponential factor representing the frequency of properly oriented, energetic collisions; its units match those of the rate constant k- How does a catalyst affect the activation energy and rate?
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A catalyst lowers Ea, increasing k without being consumed; it provides an alternative reaction pathway but does not appear in the overall rate law- What is the linear form of the Arrhenius equation used for calculations?
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ln(k) = -(Ea/R)*(1/T) + ln(A); plotting ln(k) vs 1/T gives a line with slope -Ea/R and y-intercept ln(A)- Write the two-point Arrhenius equation.
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ln(k2/k1) = (Ea/R)*(1/T1 - 1/T2); used to find Ea or predict k at a new temperature
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