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Question:Rusting Iron: 4Fe + 3O2 = 2Fe2O3 If you have a 1.50 mol sample of iron, how many moles of Fe2O3 will there be after the iron has rusted completely?

Answers:No, No, No. The rusting of iron REQUIRES water. The formula for the most common form of rust is FeO(OH). 4Fe(s) + 3O2(g) + 2H2O(l) --> 4FeO(OH)(s) You have the equation for the "combustion" of iron. 4Fe + 3O2 = 2Fe2O3 Because the mole ratio (as given by the balanced chemical equation) is 4:2 (2:1), 1.50 mol of Fe will produce half as many moles of Fe2O3, 0.750 mol Fe2O3. 1.50 mol Fe x (1 mol Fe2O3 / 2 mol Fe) = 0.750 mol Fe2O3

Question:Why?

Answers:Yes it is a chemical reaction. It is the reaction of iron with oxygen in the presence of water in what is known as oxidation. When something is oxidized, it loses electrons to what is known as a reducing agent. In this case, oxygen is the reducing agent and it is essentially stealing electrons from the iron.

Question:For example, what would be the chemical reaction (as simple as can be) of an iron nail rusting?

Answers:The rusting of iron is an electrochemical process that begins with the transfer of electrons from iron to oxygen.The rate of corrosion is affected by water and accelerated by electrolytes, as illustrated by the effects of road salt (calcium chloride) on the corrosion of automobiles. The key reaction is the reduction of oxygen: O2 + 4 e- + 2 H2O 4 OH- Because it forms hydroxide ions, this process is strongly affected by the presence of acid. Indeed, the corrosion of most metals by oxygen is accelerated at low pH. Providing the electrons for the above reaction is the oxidation of iron that may be described as follows: Fe Fe2+ + 2 e The following redox reaction also occurs in the presence of water and is crucial to the formation of rust: 4 Fe2+ + O2 4 Fe3+ + 2 O2 Additionally, the following multistep acid-base reactions affect the course of rust formation: Fe2+ + 2 H2O -> Fe(OH)2 + 2 H+ Fe3+ + 3 H2O -> Fe(OH)3 + 3 H+ as do the following dehydration equilibria: Fe(OH)2 -> FeO + H2O Fe(OH)3 ->FeO(OH) + H2O 2 FeO(OH) Fe2O3 + H2O

Question:and how do you represent them in a word equation ? Pleasee helpp as soon as possiblee :)

Answers:Rusting of iron EXPLANATION OF THE RUSTING OF IRON When iron rusts a spontaneous redox reaction occurs, between the oxygen and iron. If water is added the rusting occurs more rapidly. Iron (s) + Oxygen(g)----------> Iron (III) oxide(s) When water is added to iron, an electrochemical cell is created that has a distinct anode and cathode. If an iron nail is placed in agar or gel in which ferric cyanide ions and phenolphthalein indicator have been placed, the ends of the nail turn blue and the middle of the nail turns red. The blue colour is caused by ferricyanide indicator reaction with the iron ions, and the red colour (pink) is due to reaction between hydroxide ions and phenolphthalein. How are these ions produced. At one spot on the nail (the Anodic site of our electrochemical cell) Iron loses electrons (is oxidized) to form iron (II) ions. Fe (s) ------> Fe2+ (aq) + 2e- At another spot on the nail the oxygen in the air combines with water and forms hydroxide ions. 1/2 O2 (g) + H2O (l) + 2e- --------> 2OH- (aq) In the presence of oxygen the iron further oxidizes at the anode (loses electrons) to become iron (III) ions. Fe 2+ (aq) ------> Fe3+ (aq) + e- The iron (III) ions and the hydroxide combine to form rust ( flaky brown substance) . 2 Fe 3+ (aq) + 6OH- (aq) -----> Fe2O3 (s) + 3 H2O (l) Notice that water is required for the reaction at the cathode but produced in the overall reaction. It therefore is acting like a homogeneous catalyst, to speed up the rusting of iron. In essence the water and oxygen make it easier for iron to rust. As with an electrochemical cells the electrons flow from the anode to the cathode. Oxygen and water are both need to speed the rusting process in metals.