Introduction to Rate Law
Caleb Thomas
7 min read
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Study Guide Overview
This study guide covers reaction rates, rate laws, and their experimental determination. It explains reaction order, the rate constant (k), and its units. It also includes practice questions and exam tips for applying these concepts, including calculating reaction rates and determining rate laws from experimental data.
#AP Chemistry: Kinetics - Rate Laws Study Guide
Hey there! Let's break down rate laws and get you feeling confident for the exam. Remember, you've got this! 💪
#Reaction Rates and Rate Laws
#What is a Rate Law?
A rate law is an equation that shows how the rate of a chemical reaction depends on the concentrations of the reactants. It's all about figuring out how much faster a reaction goes when you add more stuff. Think of it as the recipe for speed! 🏎️
The general form of a rate law is:
Where:
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R = Reaction Rate (often Δ[]/Δt)
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k = Rate Constant (temperature-specific)
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[A], [B] = Concentrations of reactants
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n, m = Reaction Orders (experimentally determined)
Rate laws can only be determined by experiments, not by looking at the balanced equation.
Remember that the rate law is determined experimentally, not by the stoichiometric coefficients of the reaction.
Think of 'R = k[A]^n[B]^m' as the Rate = k times the concentration of reactants to their orders.
#Reaction Order Explained
Reaction order tells us how the rate changes when we change the concentration of a reactant. It's the exponent in our rate law equation. 📈
- If the reaction is first order with respect to a reactant (e.g., [A]¹), doubling the concentration doubles the rate.
- If it's second order (e.g., [A]²), doubling the concentration quadruples the rate.
- And so on... (tripli...
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