Chemical properties are characteristics of substances that can be observed when participating in the meaning of chemical reactions . Examples of chemical properties include flammability, toxicity, chemical stability, and combustion heat. Chemical properties are used to make chemical classifications, which are used in labels on containers and storage areas. The thing we need to remember is that chemical changes must occur so that chemical properties can be observed and measured. For example, iron is oxidized and becomes rust.
Rust is not a trait that can be explained based on pure elemental analysis. Chemical properties are very attractive to material science. These characteristics help scientists classify samples, identify unknown substances, and purify substances.
table of contents
- Chemical Properties
- Definition of Chemical Properties
- Understanding Chemical Properties According to Experts
- Examples of Chemical Properties
- Toxicity (Toxicity)
- The ability to oxidize
- Radioactivity (Radioactivity)
- Chemical stability
- Standard Enthalpy Formation
- Heat from Combustion (Heat of Combustion)
- Coordination Number
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- Definition of Chemical Properties
Chemical properties are among the material properties that become apparent during, or after, chemical reactions; that is, any quality that can be determined only by changing the chemical identity of a substance. Simply put, chemical properties cannot be determined just by looking or touching a substance; the internal structure of a substance must be greatly affected for its chemical properties to be investigated. When a substance undergoes a chemical reaction, its properties will change drastically, resulting in chemical changes.
Chemical properties can be contrasted with physical properties, which can be seen without changing the structure of substances. However, for many traits within the scope of physical chemistry, and other scientific disciplines at the boundary between chemistry and physics, the difference may be a matter of the researcher’s perspective.
Material properties, both physical and chemical, can be seen as supervenient; that is, secondary to the underlying reality.
Knowing the specific properties of a substance helps chemists make predictions about the type of reaction expected. Because chemical properties are not easily visible, they are included in labels for chemical containers. Hazard labels based on chemical properties must be affixed to the container, while complete documentation must be maintained for easy reference.
Definition of Chemical Properties
Chemical properties can be defined as the characteristics or behavior of a substance that can be observed when the substance undergoes chemical changes. Chemical change is a type of change that also changes the identity of a substance due to damage and the formation of new chemical bonds.
Chemical changes and chemical properties that can be produced are directly related to the physical properties of a substance. Some common physical properties are odor, density, melting and boiling points.
Understanding Chemical Properties According to Experts
The definition of chemical properties according to experts, include:
Chemical properties are characteristics of a material that become clear when the material undergoes a chemical reaction or chemical change. One cannot observe chemical properties just by looking or touching a sample of material; the actual material structure must be changed so that people can observe their chemical properties.
Chemical properties are characteristics or properties of a substance that can be observed when undergoing chemical changes or reactions. The chemical properties are seen during or following the reaction because the arrangement of atoms in the sample must be disturbed for the property to be investigated. This differs from physical properties, which are characteristics that can be observed and measured without changing the chemical identity of the specimen.
Examples of Chemical Properties
Here are some examples of the chemical properties of a substance, including:
1. Flammability (Flammability)
How easily a substance will burn is chemical because we cannot know it just by seeing how easily it will burn. Fire testing is carried out to determine how difficult or easy it is to get certain materials to burn.
Examples of flammable substances are white phosphorus, hydride, acetylene, CaC2, Ca3P2, ether, alcohol, acetone, benzene, sodium metal.
2. Toxicity (Toxicity)
How much a substance can damage animals, plants, cells, organs, or other organisms is its toxicity. Materials with chemical properties of toxicity include lead, chlorine gas, hydrofluoric acid, and mercury.
Toxicity is measured by how lead, chlorine gas, mercury or other substances affect the organism – basically what is measured is how much damage occurs to the organism and how quickly the damage occurs.
For example, lead is a toxic substance that can damage various parts of the human body, including bones, heart, kidneys, intestines, and nervous and reproductive systems.
3. The ability to oxidize
Each element has a set of oxidation states or oxidation states. This is a measure of the loss of electrons or oxidation of atoms in a compound.
Although integers (for example, -1, 0, 2) are used to describe the state of oxidation, the actual level of oxidation is more complicated. Because oxidation cannot be known until an element participates in a chemical reaction to form bonds.
An example is rust. Over time, iron and steel (made of iron) will rust. However, they will rust faster when combined with pure oxygen. Other examples of oxidation include the way apples turn brown after being cut.
4. Radioactivity (Radioactivity)
Radioactivity is spontaneous radiation emission. This is done by the nucleus of the atom which, for some reason, is unstable; he “wants” to release energy to move to a more stable configuration. During the first half of the twentieth century, much of modern physics was devoted to exploring why this happened, with the result that nuclear decay was well understood in the 1960s.
Radiation emissions from atoms with unstable nuclei, are chemical properties. In the periodic table of elements, elements that do not have stable isotopes are considered radioactive. Some radioactive elements are hydrogen, beryllium, carbon, calcium, cobalt, zinc and iron.
5. Chemical stability
This chemical nature in a particular environment, also called the thermodynamic stability of a chemical system, refers to the stability that occurs when a chemical system is in the lowest energy state – a state of chemical balance, or balance, with its environment. This balance will last indefinitely unless something happens to change the system.
Chemical stability is related to chemical reactivity. While chemical stability is related to a specific set of circumstances, reactivity is a measure of how likely a sample is to participate in a chemical reaction under various conditions and how quickly the reaction can proceed.
Solubility is defined as the maximum amount of a substance that can dissolve in other substances. This is the maximum amount of solute that can be dissolved in a solvent at equilibrium, which results in a saturated solution.
When certain conditions are met, additional solutes can be dissolved outside the equilibrium solubility point, which results in a saturated solution. Beyond saturation, adding more solutes does not increase solution concentration. Instead, excess solutes begin to precipitate from the solution.
In the general case, solutes are solids (for example, sugar, salt) and solvents are liquids (eg, water, chloroform), but solutes or solvents can be gases, liquids, or solids. The solvent can be a pure substance or a mixture.
Electronegativity is a property of an atom that increases with its tendency to attract electrons from a bond. If two atoms are bonded with the same electronegativity value, they share electrons evenly in a covalent bond .
Normally, electrons in chemical bonds are more attracted to one atom (which is more electronegative) than another. This produces polar covalent bonds. If the electronegativity value is very different, the electrons will not be shared at all. One atom basically takes bonding electrons from other atoms, forming ionic bonds.
For example, the chlorine atom has a higher electronegativity than a hydrogen atom, so the bonding electron will be closer to Cl than to H in the HCl molecule. In O2 molecules, both atoms have the same electronegativity. Electrons in covalent bonds are evenly divided between two oxygen atoms.
8. Standard Enthalpy Formation
Standard enthalpy formation refers to the change in enthalpy when a mole of a compound is formed from its elements. The enthalpy change that accompanies the formation of a mole of compounds from its elements, with all substances in their standard state; also called “standard heat formation.”
In chemistry, the standard state of a substance, be it a pure substance, mixture, or solution, is a reference point used to calculate its properties under different conditions. In principle, the choice of standard state is arbitrary, although the International Union of Pure and Applied Chemistry (IUPAC) recommends a set of standard states for general use. Standard pressure of 1 bar (101.3 kilopascals) has been received.
9. Heat from Combustion (Heat of Combustion)
The heating value (or energy value) of a substance, usually fuel or food, is the amount of heat released during combustion of a certain amount. The heating value is the total energy released as heat when a substance is completely combusted with oxygen under standard conditions.
Chemical reactions usually mean hydrocarbons or other organic molecules that react with oxygen to form carbon dioxide and water and release heat. That can be stated by the amount: energy / mole of fuel; energy / mass of fuel; energy / fuel volume.
There are two types of combustion heat, which are called higher and lower heating values, depending on how much product is allowed to cool and whether a compound such as H 2 O is allowed to condense. Values are measured conventionally with a bomb calorimeter.
10. Coordination Number
In chemistry, crystallography, and material science, coordination numbers, also called ligancy , from the center of atoms in a molecule or crystal are the number of atoms, molecules or ions that are attached to it. The ion / molecule / atom that surrounds the central ion / molecule / atom is called a ligand. This number is determined somewhat differently for molecules than for crystals.
For polyatomic molecules and ions, the coordination number of an atom is determined only by counting the other atoms that are bound (by single or double bonds). For example, [Cr (NH3) 2Cl2Br2] – has a central cation of Cr3 +, which has a coordination number 6 and is described as hexacoordinate .