Question

Define these terms: (a) element, (b) compound.

Short answer

An element is a pure, basic form of matter that cannot be further simplified, while a compound is a substance formed when two or more elements chemically bond together in a fixed ratio.

Step-by-step solution

Define Element

An element is a pure substance that cannot be broken down into simpler substances by any physical or chemical means. Elements are represented in the periodic table, and each one has a unique atomic structure. It is a basic form of matter that cannot be simplified further using any chemical reaction.

Define Compound

A compound is a substance formed when two or more elements are chemically bonded together. The elements in a compound combine in a fixed ratio, and the compound has properties different from those of the composing elements. Compounds can be broken down into simpler substances through chemical reactions.

Key concepts

Elements

An element is a fundamental substance that makes up matter. It is pure and cannot be broken down into simpler substances by either physical or chemical processes.

Every element is distinguished by its atomic structure, which includes a specific number of protons in its atomic nuclei. This distinct number of protons gives the element its identity, such as hydrogen with one proton or oxygen with eight.

Each element is uniquely represented in the periodic table, a comprehensive chart displaying all known elements. Thus, understanding elements is crucial for grasping the basics of chemistry.

Periodic Table

The periodic table is an organized chart that showcases all the known elements based on specific properties. This powerful tool allows scientists and students alike to discern patterns and relationships among elements.

• Elements are organized in order of increasing atomic number, which is the count of protons in an atom's nucleus.
• Rows in the table are called periods, while columns are referred to as groups or families. Elements in the same group often share similar chemical properties.
• The layout helps predict an element's behavior by describing characteristics such as reactivity and atomic size.

The periodic table is vital for studying and understanding both elements and compounds, as it serves as a roadmap of chemical behavior and interactions.

Atomic Structure

Atomic structure refers to the arrangement of particles within an atom. An atom is the smallest unit of an element, consisting of subatomic particles: protons, neutrons, and electrons.

• Protons are positively charged particles found in the nucleus, contributing to the atom's identity and its atomic number.
• Neutrons are neutral particles also located in the nucleus; they add mass to the atom and influence stability.
• Electrons are negatively charged particles orbiting the nucleus in energy levels or shells.

The number and arrangement of these subatomic particles determine not only the element itself but also its chemical properties and reactions. Understanding atomic structure is essential for delving deeper into how elements form compounds and engage in chemical processes.