Iron is an easily oxidized metal because it does not hold its electrons with a very strong bond. In this case, Iron is the reducing agent, because it loses electrons. Chlorine is the oxidizing agent, because it gains electrons. We know the byproduct of this reaction as rust. Rust is iron oxide—Fe OH 2 —and depending on factors like pH and salts, it comes in many forms.
In fact, there are 16 different forms of iron oxide. We are not chemists, so this is complex stuff that we will simplify for our audience. But before we do, the following formula is one example of what it looks like when chlorine oxidizes iron :. All you need to know is this: water, oxygen and the strong form of chlorine in a pool HOCl all oxidize iron, creating iron oxide rust.
In the water, that iron oxide can stay suspended in solution, or it can fall out of solution and stain. Naturally, that stain will be rust-colored. A common question we get is the difference between chelation and sequestration. Most metal control products in the pool industry are sequestering agents , and most of those sequestering agents are phosphate-based phosphonic or phosphoric acid.
Orenda's metal control product, SC , is a chelating agent that contains no phosphates at all. Sequestration is kind of like a magnet. A sequest attracts electrons from metals and minerals like calcium.
When they bond with the sequestering agent, these metals cannot be oxidized, and calcium cannot bond to carbonate ions to form calcium carbonate scale or dust. The metals and minerals are held in suspension not solution , and sometimes the clusters are large enough to be filtered out. These amazing benefits are why phosphate-based sequestering agents are added to drinking water Chelation divides and conquers.
Rather than attracting a whole bunch of metals and clumping them together, chelating agents divide up and attract individual ions of metals and minerals. Chelation occurs ion by ion, and holds metals and minerals in solution not suspension.
This is preferred for minerals like calcium, but is a disadvantage for trying to filter out and remove metals. Chelated metals tend to pass right through filters, because they are not sequestered together. Here is our marvelously over-simplified diagram that attempts to illustrate the difference between sequestration and chelation:. Some metals can both sanitize and be oxidized. Let's take copper as one example. Copper is a popular product in the pool business because it can be a strong algaecide.
This can occur because copper can both be oxidized AND sanitize. It's great for a quick kill against algae, but copper algaecides leave behind [you guessed it] copper. The EPA limits for copper levels in drinking water , and because of that eventual toxicity, Orenda recommends against regular use of copper products.
Yes, even if the copper algaecide is chelated. It stays in the water long-term, and if you remember, Orenda's philosophy is Proactive pool care without chemical conflicts or long-term byproducts. There are popular metal-based systems on the market in the swimming pool business, and most of them are very effective at keeping pools clean and sanitized.
These systems are usually referred to as mineral systems, and they work by allowing the metal to be dissolved into water, intentionally. Normally these metals are already chelated before they are introduced into the water. Copper and Silver are two of the most popular mineral systems available. There are certainly benefits to using mineral systems, like how long they last, and how easy they are to use. Oxidation according to Dictionary. Oxidizing is: to convert an element into an oxide; combine with oxygen.
What Causes Oxidation? How Do You Prevent Oxidation? Related Post. How to Clean Chrome with Sheen Genie When it comes to chrome, it is important to take care of it or it can deteriorate and quickly look dull and dingy. The best…. Metal Polish: The One Product You Need As with any product, there are many varieties of metal polish that will give many varieties of results or the lack of results in some…. Tips on Cleaning and Polishing Chrome Wheels Chrome wheels are a must if you want your car to stand out, so you may want to try replacing your existing wheels.
Mirror finish…. Recent Posts. This is, however, an average oxidation state for the two carbon atoms present. Because each carbon atom has a different set of atoms bonded to it, they are likely to have different oxidation states.
To determine the oxidation states of the individual carbon atoms, we use the same rules as before but with the additional assumption that bonds between atoms of the same element do not affect the oxidation states of those atoms. The oxidation states of the individual atoms in acetic acid are thus. Many types of chemical reactions are classified as redox reactions, and it would be impossible to memorize all of them. However, there are a few important types of redox reactions that you are likely to encounter and should be familiar with.
These include:. The following sections describe another important class of redox reactions: single-displacement reactions of metals in solution. A widely encountered class of oxidation—reduction reactions is the reaction of aqueous solutions of acids or metal salts with solid metals. When an object rusts, iron metal reacts with HCl aq to produce iron II chloride and hydrogen gas:.
Some of these reactions have important consequences. For example, it has been proposed that one factor that contributed to the fall of the Roman Empire was the widespread use of lead in cooking utensils and pipes that carried water. Rainwater, as we have seen, is slightly acidic, and foods such as fruits, wine, and vinegar contain organic acids. In the presence of these acids, lead dissolves:. Consequently, it has been speculated that both the water and the food consumed by Romans contained toxic levels of lead, which resulted in widespread lead poisoning and eventual madness.
Perhaps this explains why the Roman Emperor Caligula appointed his favorite horse as consul! Certain metals are oxidized by aqueous acid, whereas others are oxidized by aqueous solutions of various metal salts. Both types of reactions are called single-displacement reactions, in which the ion in solution is displaced through oxidation of the metal.
By observing what happens when samples of various metals are placed in contact with solutions of other metals, chemists have arranged the metals according to the relative ease or difficulty with which they can be oxidized in a single-displacement reaction. For example, metallic zinc reacts with iron salts, and metallic copper reacts with silver salts. Zinc therefore has a greater tendency to be oxidized than does iron, copper, or silver. Although zinc will not react with magnesium salts to give magnesium metal, magnesium metal will react with zinc salts to give zinc metal:.
The metals at the top of the series, which have the greatest tendency to lose electrons, are the alkali metals group 1 , the alkaline earth metals group 2 , and Al group In contrast, the metals at the bottom of the series, which have the lowest tendency to be oxidized, are the precious metals or coinage metals—platinum, gold, silver, and copper, and mercury, which are located in the lower right portion of the metals in the periodic table.
You should be generally familiar with which kinds of metals are active metals, which have the greatest tendency to be oxidized. When using the activity series to predict the outcome of a reaction, keep in mind that any element will reduce compounds of the elements below it in the series. Similarly, the precious metals are at the bottom of the activity series, so virtually any other metal will reduce precious metal salts to the pure precious metals.
Hydrogen is included in the series, and the tendency of a metal to react with an acid is indicated by its position relative to hydrogen in the activity series. Only those metals that lie above hydrogen in the activity series dissolve in acids to produce H 2. Because the precious metals lie below hydrogen, they do not dissolve in dilute acid and therefore do not corrode readily. Using the activity series, predict what happens in each situation.
If a reaction occurs, write the net ionic equation. Recall from our discussion of solubilities that most nitrate salts are soluble. In this case, the nitrate ions are spectator ions and are not involved in the reaction. Corroded battery terminals. The white solid is lead II sulfate, formed from the reaction of solid lead with a solution of sulfuric acid.
Oxidation—reduction reactions are balanced by separating the overall chemical equation into an oxidation equation and a reduction equation. In oxidation—reduction reactions, electrons are transferred from one substance or atom to another.
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