lecture4 - Chemical kinetics Chemical kinetics Chemical...

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Chemical kinetics
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Chemical kinetics Chemical kinetics is the study of rates of chemical reactions and what factors affect the rate of reactions. These factors include concentration, temperature, pressure, surface area, and the effect of a catalyst.
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rate of reaction rate of reaction is used to denote the measure of the rate at which the products are formed in a time interval or the rate at which the reactants are consumed over a time interval. A reaction rate measures how fast or how slow a reaction is
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Symbolically, the reaction rate is given the letter in expressions. Therefore to write the expression for the reaction rate, you can write the following. K=Δ concentration/Δ time
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Remember that the symbol Δ means the change in . Sample question: For the reaction H2(g) + I2(g) 2 HI(g), under certain conditions the [HI] = 0.50 mol/L at 25 s and 0.75 mol/L at 40 s. What is the rate of production of HI K=ΔH/Δt =(0.75−o.5)mol/L/(40-25)s =0.25mol/L/15s
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summary Chemical kinetics is the study of rates of chemical reactions and how factors affect rates of reactions. The term rate of reaction is used to denote the measure at which the products are formed over a time interval or the rate at which the reactants are consumed over a time interval. The units to measure the reaction rate are in mol/L·s. Instantaneous rate is
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Graphing Instantaneous Rate Instantaneous rate is defined as the rate of change at a particular moment For reactions, the instantaneous rate is the rate of the reaction at a specific time in the reaction sequence. 1. As the reaction proceeds, the concentration of the reactants decreases over time. If you were to graph the rate of the
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Graphing Instantaneous Rate Figure 1: Graph of Concentration vs Time.
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Instantaneous rate To find the instantaneous rate, or the rate at any given time in the reaction, a tangent line is drawn to this curve. Then the slope of the tangent line is found for a point on the curve. For example, we wanted to know the instantaneous rate at t = 2 s. After drawing the tangent line (see Figure 2), we can calculate the slope of the tangent line to find the instantaneous rate at t = 2 s.
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Figure 2: Graph of Concentration vs Time With Tangent Line.
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Y2-y1/x2-x1 =0.35-0.63/3-1 =0.28mol/L/2s or rate = 0.14 mol/L·s since the rate decreases with time for reactants.
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Lesson Objectives Define the collision theory. Describe the conditions for successful
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lecture4 - Chemical kinetics Chemical kinetics Chemical...

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