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. C 3 H 8 , better known as propane, undergoes combustion. The balanced equation is:. 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.
Sometimes, with limited oxygen, the reaction will occur, but it produces carbon monoxide CO or even soot. In that case, it is called incomplete combustion. 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.
As a result, sulfur dioxide is released, which is a pollutant. Coal with lower sulfur content is more desirable, but more expensive, because it will release less of the sulfur-based pollutants.
Organic reactions occur between organic molecules molecules containing carbon and hydrogen. Since there is a virtually unlimited number of organic molecules, the scope of organic reactions is very large.
However, many of the characteristics of organic molecules are determined by functional groups —small groups of atoms that react in predictable ways. Another key concept in organic reactions is Lewis basicity. Parts of organic molecules can be electrophillic electron-loving or nucleophillic nucleus, or positive loving. Nucleophillic regions have an excess of electrons—they act as Lewis bases—whereas electrophillic areas are electron deficient and act as Lewis acids.
The nucleophillic and electrophillic regions attract and react with each other. Organic reactions are beyond the scope of this book, and are covered in more detail in Organic Chemistry. However, most organic substances can undergo replacement reactions and combustion reactions, as you have already learned.
This is exactly what happens in a redox reaction, one species is reduced and another is oxidized. Reduction involves a gain of electrons and oxidation involves a loss, so a redox reaction is one in which electrons are transferred between species. Reactions where something is "burnt" burning means being oxidised are examples of redox reactions, however, oxidation reactions also occur in solution, which is very useful and forms the basis of electrochemistry.
Redox reactions are often written as two half-reactions showing the reduction and oxidation processes separately. These half-reactions are balanced by multiplying each by a coefficient and added together to form the full equation.
When magnesium is burnt in oxygen, it loses electrons it is oxidised. Conversely, the oxygen gains electrons from the magnesium it is reduced. Redox reactions will be discussed in greater detail in the redox section. From Wikibooks, open books for an open world. Category : Book:General Chemistry. Namespaces Book Discussion. Views Read Edit Edit source View history. Reading room forum Community portal Bulletin Board Help out!
Policies and guidelines Contact us. Add links. General Chemistry. Synthesis reactions always yield one product. Answers: 2. Answer from: anatomyfl. A synthesis reaction is a type of direct combination reaction in which multiple reactants combine to form a single product.
In a synthesis reaction two or more chemical compound combine to form a more complex product. An example is the synthesis of water from H2 and Answer from: antome. Answer from: asiamuhammad6. B Explanation: Synthesis is addition, and think of the letters as variables. Other questions on the subject: Physics. Physics, Which of the following is the result of the nuclear weak force? Agas expands from an initial volume of 0. In three hundred words or more, compare the different stages of love the speakers experience in Teadale's three poems "Dew," "Lights," and "I Shall Not Care.
Write an equation to match this graph. Pls help! The ratio of cement to gravel in a road surface is Find the percent of cement in the mixture
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