عنوان البحث(Papers / Research Title)
THE EFFECT OF PH ON THE COPPER DISPLACEMENT
الناشر \ المحرر \ الكاتب (Author / Editor / Publisher)
زهير طالب خليف الطائي
Citation Information
زهير,طالب,خليف,الطائي ,THE EFFECT OF PH ON THE COPPER DISPLACEMENT , Time 5/11/2011 6:58:45 AM : كلية هندسة المواد
وصف الابستركت (Abstract)
REACTION IN SIMPLE ELECTRICAL CELLS
الوصف الكامل (Full Abstract)
A displacement reaction is an important oxidation and reduction reactions consists of those in which an element reacts with a compound, entering into combination with one of the constituents and freeing the other. This study reports on the effect of PH solution on the copper displacement reaction. Low carbon steel (0.14%c), pure aluminum ( 99 % ), and aluminum alloy (G3/5052) used as substrate for deposition copper from its aqueous solution of varying PH.The results show Cu deposit from its aqueous solution, and rate of deposition increase with decreasing the value of PH of the aqueous Copper solution.
INTRODUCTION: A displacement reaction is the chemical change which occurs when a more reactive element displaces a less reactive element from its compounded, for example in displacement reaction such as: + + if M>Cu (1)in such redox reaction, electrons are transferred from metal atoms to Copper (II) ions because the metal is more reactive than Copper (i.e., the metal is more easily oxidation) the redox half equations are: + (Oxidation) (2) (Reduction) All single displacement reactions have the general form : Here: ( 3 ) A is an element and BC is usually an aqueous ionic compound or an acid ( consisting of B and C aqueous ion ) . A displaces B in BC , resulting in the formation of new element B and a new ionic compound or acid , AC. If the new element B is a metal , it will appear as a metallic deposit. If it is a gas , it will appear as bubbles .An Activity Series of elements is often used to determine if A will displace B in a single displacement reaction . As a rule , if A has a higher activity that B , a Single displacement reaction will occur . However , if A has lower activity than B , a single displacement reaction will not occur . The rate and overall performance of displacement reaction can be dependent on : 1- Chemical composition ( liqands , PH ,etc ) . The more strongly complexed an ion ,that harder it is to reduce , PH can affect complexation and overall chemical and electrochemical reaction . 2- Physical properties ( temperature , agitation , or mass transport ). High temperature and agitation results in higher rates and uniformity . 3- Electrochemical properties of the metal ion ( the standard potential ,the charge on the ion , the rate of electron transfer . The independent variables known to effect on the displacement reaction include concentration, temperature, surface area, PH of solution, and the catalysts. In simple electrical cells, a potential difference (v) is absorbed if the metal (M) is more or less reactive than copper. [......., Ca> Mg> Al > Mn > Zn > Fe > Ca > Ni> Sn > (H) > Cu > Ag ] . The metallic calcium will displace any of the other metals in the list ; whereas gold will not displace but will be displaced by any of the of others . As a corollary it may be pointed out that only those metals that precede hydrogen in the displacement series would be expectation , indeed is borne out by experiment . Hydrogen can not be obtained , for example , by the action of an acid upon metallic copper
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