chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15-16-hy2x7m5uokc

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Complex or composite reactions</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>Detection of reaction intermediates</p>
</li>
<li>
<p>Difficult to identify intermediates</p>
</li>
<li>
<p>Form of experimental rate equation</p>
</li>
</ul>
<ul>
<li>
<p>$ClO^-(aq)+I^-(aq) \rarr Cl^-(aq)+IO^-(aq)$</p>
</li>
<li>
<p>$r = k[ClO^-][I^-]$</p>
</li>
<li>
<p>$r = k\frac{[ClO^-][I^-]}{[OH^-]}$</p>
</li>
</ul>
<ul>
<li>Reaction is composite or complex in nature</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-025-0151.2.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> <span style="color:blue">Complex or composite reactions</span> $\rightarrow$ Termolecular reaction $\rightarrow$ Rate-limiting step </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Complex or composite reactions</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>$2Cu^{2+}(aq)+H_2(g) \rarr 2Cu^+ (aq) + 2H^{-1}(aq)$</li>
</ul>
<ul>
<li>Experimentally observed</li>
</ul>
<ul>
<li>$r=\frac{k[Cu^{2+}]^2 [H_2]}{k’[Cu^{2+}] + k’’[H^+]}$</li>
</ul>
<ul>
<li>Where k, k’ ,k" is constants</li>
</ul>
<ul>
<li>$r=k[Cu^{2+}]^2[H_2]$</li>
</ul>
<ul>
<li>
<p>Had the reaction been an elementary reaction</p>
</li>
<li>
<p>The reaction is a composite reaction</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-103-0573.6.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> <span style="color:blue">Complex or composite reactions</span> $\rightarrow$ Termolecular reaction $\rightarrow$ Rate-limiting step </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Termolecular reaction</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>$2Cu^{2+} + H_2$</p>
</li>
<li>
<p>$Cu^{2+} + Cu^{2+} + H_2$</p>
</li>
</ul>
<ul>
<li>Would have to collide simultaneously so that the reaction is single step in nature</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-169-0902.4.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-03.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-103-0573.6.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ <span style="color:blue">Termolecular reaction</span> $\rightarrow$ Rate-limiting step </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p><strong>Rate determining step</strong></p>
</li>
<li>
<p><strong>Reaction Mechanism</strong></p>
</li>
</ul>
<ul>
<li>
<p>$A \xrightarrow{k_1} X \hspace{4 mm} r_1=k_1[A]$</p>
</li>
<li>
<p>$X \xrightarrow{k_2} Y \hspace{4 mm} r_2=k_2[X]$</p>
</li>
<li>
<p>$Y \xrightarrow{k_3} P \hspace{4 mm} r_3=k_3[Y]$</p>
</li>
<li>
<p>$A \rarr P$</p>
</li>
</ul>
<ul>
<li>Each step has its own rate</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-04.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>If you were trying to analyse the reaction by looking at the formation of P</p>
</li>
<li>
<p>Difficult and complex</p>
</li>
</ul>
<ul>
<li>
<p>P depends on Y</p>
</li>
<li>
<p>Y depends on X</p>
</li>
<li>
<p>X depends on A</p>
</li>
</ul>
<ul>
<li>Complicated picture</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-05.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-307-1464.0.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>Many rate expressions are quite simple</p>
</li>
<li>
<p>How do we decide on which step the final rate of reaction will depend upon ?</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-351-1639.2.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-307-1464.0.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:60%;font-size:22px;text-align:left'>
<ul>
<li>
<p>Rate Determining step</p>
</li>
<li>
<p>Rate Limiting step</p>
</li>
</ul>
</div>
<div style='float: right; width:40%;'>


<p><img alt="alt text" src="https://imagedelivery.net/YfdZ0yYuJi8R0IouXWrMsA/25c9a305-5037-4d22-6310-2b6cf3fbfd00/public"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>$A\rarr P$</p>
</li>
<li>
<p>$r=k_1[A]$ because</p>
</li>
<li>
<p>$A \rarr X \rArr$ Slowest step rate determining step</p>
</li>
</ul>
<ul>
<li>
<p>It does not matter how fast the other steps are</p>
</li>
<li>
<p>If the first step is the rate determining step, then the rate of the overall reaction will only depend on the first step</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-483-2247.6.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li><strong>For step 1 being rate-limiting</strong></li>
</ul>
<ul>
<li>
<p>$r=k[ClO^-][ClO^-]$</p>
</li>
<li>
<p>$r=k[ClO^-]^2$</p>
</li>
<li>
<p>$r_{exp}=k[ClO^-]^2$</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-549-2515.2.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-06.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>Possible reaction mechanism</li>
</ul>
<ul>
<li>
<p>$2NO_2(g) +F_2(g) \rarr 2NO_2F(g)$</p>
</li>
<li>
<p>$r_{exp}=k[NO_2][F_2]$</p>
</li>
<li>
<p>Slow $NO_2 + F_2 \rarr NO_2F + F$</p>
</li>
<li>
<p>$NO_2 + F \rarr NO_2F$</p>
</li>
<li>
<p>$r=k[NO_2][F_2]$</p>
</li>
<li>
<p>Possible mechanism</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-613-2780.4.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-06.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>$A \rightleftarrows X$ (Step-1)</li>
</ul>
<ul>
<li>At equilibrium</li>
</ul>
<ul>
<li>
<p>$k_1[A]=k_{-1}[X]$</p>
</li>
<li>
<p>$[X]=\frac{k_1}{k_{-1}}[A]$</p>
</li>
<li>
<p>$k_{eq}=\frac{[X]}{[A]}=\frac{k_1}{k_{-1}}$</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-718-3218.4.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-07.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>

<p><Success style="float:center;text-align:center;font-size:28px;"> <B>Chemical kinetics Lecture-15</B></Success></p>
<p><primary style="float:center;text-align:center;font-size:24px;"> <B>Rate-limiting step</B></primary></p>
<hr>
<main>
<div style='float: left; width:100%;font-size:22px;text-align:left'>
<ul>
<li>
<p>$r=k_2[B][X]$</p>
</li>
<li>
<p>$r=k_2[B]\frac{k_1}{k_{-1}}[A]$</p>
</li>
<li>
<p>$r=k_2\frac{k_1}{k_{-1}}[B][A]$</p>
</li>
<li>
<p>$r=k_2k_{eg}[A][B]$</p>
</li>
</ul>
</div>
<div style='float: right; width:0%;'>
<p><img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-734-3273.6.jpg">
<img alt="image" src="/subject-images/iitpal/image/chemistry-class-12-unit-04-chapter-15-chemical-kinetics-l-15_16-hy2x7m5uokc-718-3218.4.jpg"></p>
</div>
</main>
<hr>
<footer style="font-size:18px;"> Complex or composite reactions $\rightarrow$ Termolecular reaction $\rightarrow$ <span style="color:blue">Rate-limiting step</span> </footer>