I'm tired of trying to make Blogger and LaTeX work nicely together. At this point, it's just becoming another way for me to procrastinate even more. So, I'm admitting defeat.
There are several different types of chemical reactions that can occur. To begin, let's start by examining the simplest--a synthesis reaction. In a synthesis reaction, multiple reactants are combined into several products. For example, iron (II) sulfide is created when iron and sulfur react.
Iron (II) sulfide is an ionic compound--this is an easy enough distinction because iron is a metal, and sulfur is a nonmetal. So we know that iron has lost two electrons to sulfur, and that the offsetting charges have resulted in a bond between the two ions. We use the (II) when naming iron (II) sulfide to distinguish it from iron (III) sulfide. This distinction is important because iron can lose either two or three electrons. In naming ionic bonds, it is important to note that prefixes are not used with the element names--only with covalent bonds.
When writing a formula for a named ionic bond--say, calcium carbonate--then a simple technique can be applied. Take each individual part of the compound--Ca and CO3, and try to find a ratio of the two ions that has an equal charge. Because a calcium ion has a charge of +2, and carbonate has a charge of -2, the ratio is simply 1:1. Calcium carbonate can be written as CaCO3.
WARNING! WARNING! WARNING! Sudden topic change ahead. Massive confusion of the brain may result.
Another type of chemical reaction (remember that? The original topic?) is a decomposition reaction. This is the inverse of a synthesis reaction, where one reactant is split into two or more different products. For example, consider the electrolysis of water, when a current is passed through water. The formula for this reaction would be: 2H2O --> 2H2 + O2. The hydrogen and oxygen contained within the water molecule become hydrogen gas and oxygen gas.
The third type of chemical reaction is a single replacement reaction. This type of reaction involves two reactants, one being a compound of two elements, the other, a single element. In a single replacement reaction, the single element will take the place of an element from the compound. A complement for the single replacement is the double replacement. A double replacement reaction is similar to a single replacement reaction, except that instead of one reactant being an element, both reactants are compounds, and one element in each compound joins the other compound. A generic example of a double replacement would be: AB + CD --> CB + AD.
Finally, there's a combustion reaction. In a combustion reaction, a fire burns in the presence of oxygen. Combustion reactions tend to be exothermic and to result in carbon dioxide and water. In its most general form, we could write: Fuel + O2 --> CO2 + H2O + heat energy.
Afterword
I suppose I should go ahead and finish this off. When naming a covalent bond from a formula, you don't have to worry about various ions. There's a simple technique you can follow. For example, consider the molecule CO2. C represents carbon, so we know that the first part of the name of this molecule is named carbon. To represent the presence of both oxygen atoms, we use the prefix di-, so this become dioxide. Putting it all together gives us carbon dioxide.
Rules were made to be broken, however, and these rules do not apply when acids are formed. When hydrogen bonds with another atom, excluding, of course, hydrogen itself and oxygen, an acid is formed. To name an acid, use the prefix hydro-, then the name of the second atom, using the suffix -ic. For example, HCl would be written as hydrochloric acid.
Exception to the exception: If the second part of the compound is a polyatomic compound (it has multiple atoms), then do not use the hydro- prefix. Instead, simply keep the name of the polyatomic compound and add the -ic suffix if it ends in -ate, and -ous if it ends in -ite.
WARNING! WARNING! WARNING! Sudden topic change ahead. Massive confusion of the brain may result.
Another type of chemical reaction (remember that? The original topic?) is a decomposition reaction. This is the inverse of a synthesis reaction, where one reactant is split into two or more different products. For example, consider the electrolysis of water, when a current is passed through water. The formula for this reaction would be: 2H2O --> 2H2 + O2. The hydrogen and oxygen contained within the water molecule become hydrogen gas and oxygen gas.
The third type of chemical reaction is a single replacement reaction. This type of reaction involves two reactants, one being a compound of two elements, the other, a single element. In a single replacement reaction, the single element will take the place of an element from the compound. A complement for the single replacement is the double replacement. A double replacement reaction is similar to a single replacement reaction, except that instead of one reactant being an element, both reactants are compounds, and one element in each compound joins the other compound. A generic example of a double replacement would be: AB + CD --> CB + AD.
Finally, there's a combustion reaction. In a combustion reaction, a fire burns in the presence of oxygen. Combustion reactions tend to be exothermic and to result in carbon dioxide and water. In its most general form, we could write: Fuel + O2 --> CO2 + H2O + heat energy.
Afterword
I suppose I should go ahead and finish this off. When naming a covalent bond from a formula, you don't have to worry about various ions. There's a simple technique you can follow. For example, consider the molecule CO2. C represents carbon, so we know that the first part of the name of this molecule is named carbon. To represent the presence of both oxygen atoms, we use the prefix di-, so this become dioxide. Putting it all together gives us carbon dioxide.
Rules were made to be broken, however, and these rules do not apply when acids are formed. When hydrogen bonds with another atom, excluding, of course, hydrogen itself and oxygen, an acid is formed. To name an acid, use the prefix hydro-, then the name of the second atom, using the suffix -ic. For example, HCl would be written as hydrochloric acid.
Exception to the exception: If the second part of the compound is a polyatomic compound (it has multiple atoms), then do not use the hydro- prefix. Instead, simply keep the name of the polyatomic compound and add the -ic suffix if it ends in -ate, and -ous if it ends in -ite.
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