CHEMICAL PROPERTIES

A chemical property is any property of a material that becomes apparent during or after a chemical reaction; that is, any property that can be established only by altering the chemical identity of a substance. Simply put, chemical qualities cannot be discovered by looking at or touching a thing; the substance’s interior structure must be significantly altered in order to explore its chemical properties. When a substance undergoes a chemical reaction, its properties undergo dramatic changes, culminating in chemical transformation. A catalytic property, on the other hand, is a chemical property.

Chemical properties can be used to develop chemical classification schemes. Additionally, they can be utilised to detect and separate or purify unknown compounds. Typically, materials science will consider the chemical properties of a substance when assessing its applications. Chemical reactions rearrange the constituent atoms of the reactants, resulting in the formation of new substances known as products. The products have features that are distinct from those of the reactants.

Chemical reactions are distinct from physical changes, such as ice melting to water or water evaporating to vapour. When a substance undergoes a physical transformation, its physical qualities change but its chemical identity remains the same.

Chemical attributes are distinguished from physical properties, which can be determined without altering the structure of the substance. However, for many features within the scope of physical chemistry and other fields on the interdisciplinary border between chemistry and physics, the difference may be subjective. Physical and chemical aspects of matter might be considered as supervenient; that is, secondary to the underlying reality. Multiple levels of supervenience are possible.

A chemical reaction always results in the formation of one or more new types of matter that are distinct from the matter that existed prior to the reaction. Rust formation is a chemical reaction, as rust is a distinct type of substance than the iron, oxygen, and water that existed prior to the rust formation. The explosion of nitroglycerin results in a chemical transformation, as the gases released are composed of entirely different types of matter than the original material. Additional examples of chemical changes include laboratory reactions (for example, copper interacting with nitric acid), all forms of combustion (burning), and food that is cooked, digested, or decomposing.

 A brief review of history

The concept of a chemical reaction stretches all the way back to approximately 250 years ago. Its beginnings can be traced back to early studies that categorised substances as elements and compounds, as well as to ideas that described how these processes occurred. The development of the concept of a chemical reaction was critical in defining modern chemistry as a science.

The earliest significant investigations in this field focused on gases. The 18th-century discovery of oxygen by Swedish chemist Carl Wilhelm Scheele and English cleric Joseph Priestley was significant. The influence of Antoine-Laurent Lavoisier, a French chemist, was particularly noteworthy, as his ideas verified the critical nature of quantitative measurements of chemical processes. Lavoisier defined 33 “elements”—substances that cannot be broken down into simpler entities—in his work Traité élémentaire de chimie (1789; Elementary Treatise on Chemistry). Lavoisier made numerous discoveries, including properly measuring the weight gained when elements were oxidised and attributing the result to the element mixing with oxygen. His writings clearly established the concept of chemical reactions involving the combination of elements, and his method inspired others to explore experimental chemistry as a quantitative discipline.

 Chemical reaction fundamental ideas-

When chemists create a new compound from other substances, they either perform a synthesis or synthesise the new material. The process of converting reactants to products is represented by a chemical equation. For instance, when iron (Fe) and sulphur (S) react, iron sulphide is formed (FeS).

Fe(s) + S(s) → FeS(s)

Iron reacts with sulphur, as shown by the + sign. The arrow indicates that the reaction results in the formation of iron sulphide, the product. The symbols (s) for solids, (l) for liquids, and (g) for gases denote the state of matter of reactants and products.

Other example of chemical reaction-

 In the presence of damp air, phosphorus pentachloride hydrolyzes to form POCl3. This chemical degrades into phosphoric acid over time.

PCl5+H2O→POCl3+2HCl

POCl3 +3H2O→H3PO4+3HCl

 When heated, it sublimates and further disintegrates producing phosphorus trichloride.

PCl5 → PCl3+Cl2

It reacts with finely partitioned metals to form metal chlorides when heated.

2Ag+PCl5→2AgCl+PCl3

It combines with natural compounds having a ‘OH’ group and creates its ‘chloro’ subordinates.

C2H5OH+PCl5→C2H5Cl+POCl3+HCl

CONCLUSION 

Chemical characteristics can be utilised to create classification schemes for chemicals. Additionally, they can be used to identify unknown chemicals and to separate or purify them from other substances. Typically, materials science will evaluate a substance’s chemical qualities when determining its applications.