Understanding Chemical Reaction

Chemical reactions are amazing reactions which happen around us. These reactions are essential to human existence, whether by human-made processes or naturally occurring in nature. It shapes our lives that every day we encounter these reactions, such as fuel burning when we cook our food when our clothes get clean because of the detergent and many more. Some of these reactions are simple and some have complex reactions. In this article, we will discuss the world of chemical reactions, their principles, types, and real-world applications.

Generally, a chemical reaction is a process where one or more substances, called reactants, are transformed into one or more different substances, known as products (Timberlake, 2017). Chemical reactions always include the chemical change in which an atom of reacting substances combines with others forming combinations with new properties, for example, iron (Fe) combines with oxygen (O₂) to form red-brown substances that we know as rust (Fe₂O₃). 

In the laboratory, under normal laboratory conditions, matter cannot be created nor destroyed or an element transforms into another element (Kotz and Treichel, 2023). It means the total mass of the reactant always remains equal to the total mass of products, according to the Law of mass conservation.

Fig.1 An illustration of the magnesium and oxygen reaction that produces magnesium oxide 

(Source: Timberlake, 2017)

The chemical reaction can be specified into several reactions based on the changes that occur.

1. Combination is a reaction that combines two or more substances to form a single compound. For example, if we burn magnesium (Mg) using oxygen (O₂), we will have magnesium oxide (MgO) as a product. (Fig.1)
2. Decomposition is a reaction in which a compound splits into simpler products, such as hydrogen peroxide (H₂O₂) decomposing to water (H₂O) and oxygen (O₂).
3. A displacement reaction is when a substance got replaced by another substance in a compound. An example is when we put a cut of zinc metal (Zn) inside hydrochloric acid (HCl), it will produce zinc chloride (ZnCl₂) and hydrogen gas (H₂).
4. Acid-base reaction occurs when an acid reacts with a base resulting in salt and water product. For example, if we react the sodium hydroxide (NaOH) with hydrochloric acid (HCl) it will produce sodium chloride (NaCl) which is a salt we use every day and water (H₂O).
5. Combustion is a reaction in which a carbon-containing compound (fuel) reacts with oxygen and produces carbon dioxide (CO₂) and water (H₂O). 

Factors that affect the chemical reaction.

1. Temperature, to speed up the reaction increasing the temperature is the solution. The higher temperature will increase the energy for molecules to collide effectively.
2. Concentration, the higher the reactant concentration means more molecules will increase the chance of molecule collision resulting in an effective reaction.
3. A catalyst is used to speed up the reaction with lower activation energy.
4. Surface area, the reaction which involves solids often goes even faster if their surface is divided, which means more surface area and exposure to reactants.

A chemical reaction is vital in the number of real-life applications, which perform by humans or naturally occur. Here are some examples of it:

1. Combustion, is the process of burning fuel with oxygen releasing energy as well as carbon dioxide and water as products.
2. Photosynthesis is a complex reaction that happens in plant leaves. This reaction combines the reactant such as carbon dioxide and water with the help of the sun to produce glucose and oxygen, which are later used by humans or other animals as their food source.

Fig.2 Photosynthesis process in a plant. (Source: Vanstone, 2020)

3. Corrosion usually occurs in metals such as iron, aluminium, nickel, etc. This reaction usually brings negative effects, such as in iron rust. However, some metal like aluminium gives protection instead.
4. In food digestion, in our body, complex compounds are broken down into smaller and simpler compounds so they will be easy to absorb and use by the cells.

To sum up, the chemical reaction is the driving force behind all the phenomena in our lives. By understanding the principles and types of these reactions, we gain knowledge about the mechanisms behind the reaction either by natural process or human-made transformations.

Glossary

Kotz, John C. and Treichel, Paul M.. “Chemical reaction”. Encyclopedia Britannica. 2023. https://www.britannica.com/science/chemical-reaction.

Timberlake, K. C. “Basic Chemistry Global Edition”. England, Pearson Education Limited. 2017.

Vanstone, E. What is photosynthesis? – Science Questions. Science Experiments for Kids.2020. https://www.science-sparks.com/what-is-photosynthesis/.

Disclaimer: This article has been reviewed by AI for grammar checking and other suggestion also by the author to re-checked, proofread and simplified to make it easier for readers to understand.

Author :
Azarya Patty
Tutor at SAGU Foundation