Question

How is an element different from a compound?

Short answer

An element is made of one type of atom, while a compound consists of two or more different atoms chemically bonded.

Step-by-step solution

Define Element

An element is a pure substance consisting of only one type of atom. It cannot be broken down into simpler substances through chemical reactions. Examples include oxygen (O), hydrogen (H), and gold (Au).

Define Compound

A compound is a substance formed when two or more different types of atoms join together in fixed proportions through chemical bonds. Compounds can be broken down into simpler substances (elements) by chemical means. Examples include water (H2O) and carbon dioxide (CO2).

Compare Composition

The fundamental difference between an element and a compound lies in their composition. An element is made up of only one kind of atom, while a compound is made up of atoms of at least two different elements chemically bonded together.

Evaluate Chemical Reactions

Observe how elements and compounds interact with chemical reactions. Elements cannot be transformed into simpler substances, whereas compounds can be decomposed into the elements that constitute them.

Real-World Examples

Consider common examples to solidify the understanding. For instance, when you have a piece of gold jewelry, it contains only gold atoms, making it an element. In contrast, table salt (sodium chloride, NaCl) is a compound because it contains sodium and chlorine atoms chemically combined.

Key concepts

Elements

Elements are fundamental substances that consist entirely of one type of atom. These are the building blocks of all matter in the universe and are listed on the Periodic Table of Elements. Some familiar examples include oxygen (O), which we breathe, and gold (Au), which is valued for its rarity and beauty.
Unlike compounds, elements cannot be decomposed into simpler substances through chemical reactions. They are as simple as it gets. Every element has unique properties, such as atomic number, which defines the number of protons in its nucleus.
To remember:

• Pure substance
• One type of atom
• Cannot be broken down further

Compounds

Compounds are substances that form when two or more different types of atoms bind together. They achieve this through chemical bonds, forming identifiable molecules or crystals. This bond changes their properties completely from the original elements.
For instance, take hydrogen and oxygen. Both are elements that, when chemically bonded together, produce water (H2O), a compound. Unlike elements, compounds can indeed be broken down into their component elements through chemical reactions, like electrolysis.
Key points to consider:

• Made of two or more types of atoms
• Fixed ratio and structure
• Can be broken down into simpler substances

Chemical Reactions

Chemical reactions are processes by which substances, called reactants, are transformed into new substances, known as products. These reactions involve breaking old chemical bonds and forming new ones. They can result in a compound breaking down into elements or new compounds forming from elements or existing compounds.
For instance, during the decomposition of water, a chemical reaction splits water molecules back into hydrogen and oxygen gases.
Important concepts include:

• Transformation of substances
• Involvement of breaking and forming of bonds
• Can convert compounds into elements

Atoms

Atoms are the smallest units of matter that retain the properties of an element. Each atom consists of a nucleus, containing protons and neutrons, surrounded by electrons.
The arrangement and number of these subatomic particles determine the atom's identity and properties.
Atoms combine in various ways to form both elements and compounds. In a compound, atoms are bonded to one another, often where they share electrons or transfer them entirely.
Key facts:

• Fundamental building blocks of matter
• Consist of protons, neutrons, and electrons
• The basis for forming elements and compounds

Chemical Bonds

Chemical bonds are powerful links between atoms that allow for the formation of compounds. They are classified mainly into ionic, covalent, and metallic bonds.
These bonds form when atoms share electrons (covalent bonds), transfer electrons (ionic bonds), or pool electrons (metallic bonds). The type of bond influences the compound's structure and properties.
For example, the water molecule possesses covalent bonds allowing hydrogen and oxygen to share electrons. Meanwhile, common table salt (NaCl) features ionic bonds between sodium and chlorine.
Quick overview:

• Holds atoms together in compounds
• Variety of types: ionic, covalent, metallic
• Determines compound properties and stability