F 2 is such a good oxidizing agent that metals, quartz, asbestos, and even water burst into flame in its presence. Other good oxidizing agents include O 2 , O 3 , and Cl 2 , which are the elemental forms of the second and third most electronegative elements, respectively. Another place to look for good oxidizing agents is among compounds with unusually large oxidation states, such as the permanganate MnO 4 - , chromate CrO 4 2- , and dichromate Cr 2 O 7 2- ions, as well as nitric acid HNO 3 , perchloric acid HClO 4 , and sulfuric acid H 2 SO 4.
These compounds are strong oxidizing agents because elements become more electronegative as the oxidation states of their atoms increase. Good reducing agents include the active metals, such as sodium, magnesium, aluminum, and zinc, which have relatively small ionization energies and low electro-negativities. Some compounds can act as either oxidizing agents or reducing agents.
One example is hydrogen gas, which acts as an oxidizing agent when it combines with metals and as a reducing agent when it reacts with nonmetals. Another example is hydrogen peroxide, in which the oxygen atom is in the -1 oxidation state.
Because this oxidation state lies between the extremes of the more common 0 and -2 oxidation states of oxygen, H 2 O 2 can act as either an oxidizing agent or a reducing agent. Corrosion requires an anode and cathode to take place. The anode is an element that loses electrons reducing agent , thus oxidation always occurs in the anode, and the cathode is an element that gains electrons oxidizing agent , thus reduction always occurs in the cathode.
When this is present, the anode metal will begin deteriorating given that there is an electrical connection and the presence of an electrolyte. These changes can be viewed as two " half-reactions " that occur concurrently:. Iron III Fe has been oxidized because the oxidation number increased and is the reducing agent because it gave electrons to the oxygen O.
Oxygen O has been reduced because the oxidation number has decreased and is the oxidizing agent because it took electrons from iron Fe. Categories: Reducing agents Chemical reactions. Read what you need to know about our industry portal chemeurope. My watch list my. My watch list My saved searches My saved topics My newsletter Register free of charge.
Keep logged in. Cookies deactivated. To use all functions of this page, please activate cookies in your browser. Login Register. Additional recommended knowledge. Topics A-Z. All topics. To top. Apparent anomalies can be explained by the fact that electrode potentials are measured in aqueous solution, which allows for strong intermolecular electrostatic interactions, and not in the gas phase.
All that is required is to add warm water and salt for electrical conductivity. From this value, determine whether the overall reaction is spontaneous. Conceptual Problems The order of electrode potentials cannot always be predicted by ionization potentials and electron affinities. Do you expect sodium metal to have a higher or a lower electrode potential than predicted from its ionization potential?
What is its approximate electrode potential? Because of the sulfur-containing amino acids present in egg whites, eating eggs with a silver fork will tarnish the fork. As a chemist, you have all kinds of interesting cleaning products in your cabinet, including a 1 M solution of oxalic acid H 2 C 2 O 4.
Would you choose this solution to clean the fork that you have tarnished from eating scrambled eggs? Is the potential for the oxidation of 0.
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