Kinetics and Mechanism of the Reaction between Chromium(III) and 3,4-Dihydroxy-Phenyl-Propenoic Acid (Caffeic Acid) in Weak Acidic Aqueous Solutions

<table>The Eyring plots for <svg height="18.325001" id="M84" style="vertical-align:-4.90039pt" version="1.1" viewbox="0 0 39.662498 18.325001" width="39.662498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,18.438,16.25)"><path d="M257 449q92 0 154 -65t62 -158q0 -112 -67 -175t-150 -63q-98 0 -158.5 66.5t-60.5 154.5q0 59 21 106.5t54.5 75.5t71 43t73.5 15zM244 416q-48 0 -81 -47t-33 -128q0 -96 38 -158t99 -62q51 0 82 43.5t31 139.5q0 91 -36 151.5t-100 60.5z" id="x6F"></path></g><g transform="matrix(.012,-0,0,-.012,24.458,16.25)"><path d="M152 404l81 35q23 10 41 10q81 0 139 -61.5t58 -149.5q0 -107 -74.5 -178.5t-176.5 -71.5q-71 0 -147 36v555q0 48 -9.5 59.5t-56.5 15.5v23q79 10 145 35v-308zM152 374v-258q0 -20 6 -35q7 -19 30 -37t58 -18q63 0 99.5 50t36.5 137q0 82 -43.5 131t-108.5 49
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<g transform="matrix(.012,-0,0,-.012,34.862,16.25)"><path d="M275 270q0 -296 -211 -440l-19 23q75 62 116.5 174t41.5 243t-42 243t-116 173l19 24q211 -144 211 -440z" id="x29"></path></g>
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<g transform="matrix(.012,-0,0,-.012,18.438,16.25)"><path d="M257 449q92 0 154 -65t62 -158q0 -112 -67 -175t-150 -63q-98 0 -158.5 66.5t-60.5 154.5q0 59 21 106.5t54.5 75.5t71 43t73.5 15zM244 416q-48 0 -81 -47t-33 -128q0 -96 38 -158t99 -62q51 0 82 43.5t31 139.5q0 91 -36 151.5t-100 60.5z" id="x6F"></path></g><g transform="matrix(.012,-0,0,-.012,24.458,16.25)"><path d="M152 404l81 35q23 10 41 10q81 0 139 -61.5t58 -149.5q0 -107 -74.5 -178.5t-176.5 -71.5q-71 0 -147 36v555q0 48 -9.5 59.5t-56.5 15.5v23q79 10 145 35v-308zM152 374v-258q0 -20 6 -35q7 -19 30 -37t58 -18q63 0 99.5 50t36.5 137q0 82 -43.5 131t-108.5 49
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<g transform="matrix(.012,-0,0,-.012,34.862,16.25)"><path d="M275 270q0 -296 -211 -440l-19 23q75 62 116.5 174t41.5 243t-42 243t-116 173l19 24q211 -144 211 -440z" id="x29"></path></g>
</svg> at the temperatures studied.</table>

Bioinorganic Chemistry and Applications

fig4

Figure 4

Figure 4: Kinetics and Mechanism of the Reaction between Chromium(III) and 3,4-Dihydroxy-Phenyl-Propenoic Acid (Caffeic Acid) in Weak Acidic Aqueous Solutions 

Figure 4 | Kinetics and Mechanism of the Reaction between Chromium(III) and 3,4-Dihydroxy-Phenyl-Propenoic Acid (Caffeic Acid) in Weak Acidic Aqueous Solutions 