Introduction to Elements and Compounds
Elements and compounds are the two forms in which pure substances exist. Elements constitute the simplest chemical substances in which all the atoms are exactly the same. Compounds are chemical substances made up of two or more elements that are chemically bound together in a fixed ratio. Chemistry is the study of the structures, physical properties, and chemical properties of material substances. It is very important to understand that all gases, liquids, and solids are not the same. All are different in terms of their composition. This is the reason why the classification of the matter is very important.
Chemically matter can be classified into 3 categories:
Here we are going to discuss two categories of the matter: Elements and Compounds
What are Elements?
We can define elements as a species of atoms which have the same number of protons in their atomic nuclei. Although an element’s atoms have the same number of protons, they can have different numbers of neutrons and hence different masses.
Isotopes: When atoms of the same element have different numbers of neutrons, they are known as isotopes. As of now, there are 118 elements, of which the first 94 are naturally occurring while the remaining 24 are synthetic elements.
Elements are complete chemical substances which relate to a single entry in the modern periodic table. Elements consist of one kind of atoms only. They cannot be broken down into simpler fragments and can exist as atoms or as molecules. Elements are represented by symbols which are assigned by IUPAC. For example, Oxygen is represented by O, Aluminium is represented by Al, etc.
Types of Elements
The elements are arranged in the periodic table and are split depending upon their groups as either metallic or non-metallic. Metallic is further classified into Main Group Metals, Transition Metals, and f-block metals. These are again further divided depending upon their properties.
Examples of Elements
Elements exist in their simplest form and cannot be broken down further. So, elements can exist in the form of ions, atoms, isotopes, molecules.
- An example of an element is Nitrogen atom(N), Nitrogen gas (N2), Nitrogen ion(N3-) and Nitrogen isotopes (Nitrogen-13, Nitrogen-14, and Nitrogen-15).
Similarly, you could see other elements’ existence.
Examples of some commonly used elements along with their chemical symbols:
|Name of the element||Chemical symbol|
What are Compounds?
When two or more elements chemically combine in a fixed ratio by mass, the obtained product is known as a compound. Compounds can be defined as substances consisting of 2 or more different types of elements in a fixed ratio of its atoms. When the elements combine, some of the individual property of the elements is lost and the newly formed compound has new properties.
Chemical Formula: Compounds are represented by their chemical formula. A chemical formula is a symbolic representation of the proportions of atoms that constitute a particular chemical compound.
The chemical formula of water is H2O which shows two atoms of hydrogen and one atom of oxygen have combined to form one molecule of H2O. The chemical formula for common salt is NaCl which shows one atom of sodium and one atom of chlorine combine to form one molecule of NaCl.
Types Of Compounds
Compounds can be classified into two types, molecular compounds, and Salts. In molecular compounds, atom binds each other through covalent bonds. In salts, it is held together with ionic bonds. These are the two types of bonds out of which every compound are made of.
Example Of Compounds
- Example of compounds includes water (H2O), Hydrogen Peroxide (H2O2) etc. You could see water’s chemical formula, it says it has 2 atoms of Hydrogen combined with 1 atom of oxygen and in hydrogen peroxide, it has 2 atoms of hydrogen and two atoms of oxygen.
- Similarly, an example of salt would be the table salt (NaCl) which has 1 atom of sodium and one atom of chlorine.
Examples of some commonly used compounds and their molecular formula:
|Compound Name||Compound Formula|
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