Types of chemical reactions with examples pdf

Please forward this error screen types of chemical reactions with examples pdf 216. Chemical reactions can be divided into several classes each having similar characteristics. These different types of reactions will be discussed in greater detail throughout the book. You will find that almost every reaction you see can fall into one of these categories, so make sure that you understand them.

Synthesis reactions always yield one product. Synthesis reactions “put things together”. This is the most well-known example of a synthesis reaction—the formation of water via the combustion of hydrogen gas and oxygen gas. Because of the very high reactivities of sodium metal and chlorine gas, this reaction releases a tremendous amount of heat and light energy. Recall that atoms release energy as they become stable, and consider the octet rule when determining why this reaction has such favorable features.

Decomposition reactions “take things apart”. Just as synthesis reactions can only form one product, decomposition reactions can only start with one reactant. Compounds that are unstable decompose quickly without outside assistance. Hydrogen peroxide slowly decomposes into water and oxygen because it is somewhat unstable.

The process is sped up by the energy from light, so hydrogen peroxide is often stored in dark containers to slow down the decomposition. Carbonic acid is the carbonation that is dissolved in soda. It decomposes into carbon dioxide and water, which is why an opened drink loses its fizz. Decomposition, aside from happening spontaneously in unstable compounds, occurs under three conditions: thermal, electrolytic, and catalytic. Single displacement reaction, also called Double replacement, is a reaction in which 2 elements are substituted for another element in a compound. The starting materials are always pure elements, such as a pure zinc metal or hydrogen gas plus an aqueous compound. When a displacement reaction occurs, a new aqueous compound and a different pure element are generated as products.

This is also called an “exchange”. An example is lead nitrate mixed with potassium iodide, which forms a bright yellow precipitate of lead iodide. Note that the lead iodide is formed as a solid. The previous equation is written in molecular form, which is not the best way of describing the reaction.

Notice the like terms on both sides of the equation. In the solution, there exists both lead and iodide ions. Because lead iodide is insoluble, they spontaneously crystallise and form the precipitate. Again, we get a clearer picture of what’s happening if we write a net ionic equation. Acid base reactions often happen in aqueous solution, but they can also occur in the gaseous state.

Combustion, better known as burning, is the combination of a substance with oxygen. The products are carbon dioxide, water, and possible other waste products. Combustion reactions release large amounts of heat. Combustion is similar to a decomposition reaction, except that oxygen and heat are required for it to occur. If there is not enough oxygen, the reaction may not occur. If the substances being burned contain atoms other than hydrogen and oxygen, then waste products will also form. Coal is burned for heating and energy purposes, and it contains sulfur.