1.Elements, Compounds and Mixtures

Element

The simplest form of matter, cannot be separated into simpler substances by chemical means.

Atomic Number

The number of protons in the nucleus of an atom, unique to each element.

Compounds

Substances formed when two or more different chemical elements are chemically bonded in a fixed ratio.

Isotope

Atoms of an element with different numbers of neutrons in the nucleus.

Relative Atomic Mass

A weighted average of the masses of the isotopes of an element based on their relative abundance.

Homogeneous Mixture

A mixture with uniform composition and properties throughout.

Heterogeneous Mixture

A mixture that does not have uniform composition and properties throughout.

Chemical Bond

The lasting attraction between atoms that enables the formation of chemical compounds.

Covalent Bond

A type of bond formed when two atoms share electrons.

Ionic Bond

A type of bond formed when one atom transfers electrons to another, resulting in charged ions.

Mixture

A combination of two or more substances that are not chemically combined and can be separated by physical means.

Periodic Table

A table that arranges chemical elements based on their atomic number and similar properties.

Chemical Symbol

A one or two-letter abbreviation used to represent a chemical element.

Fixed Ratio

A specific and constant ratio of elements in a compound.

Energy Change

A change in energy that occurs during a chemical reaction or physical process.

Physical Separation Methods

Techniques used to separate mixtures into their individual components without chemical reactions.

Hydrocarbon

Compounds composed only of hydrogen and carbon.

Vinegar

A liquid consisting of acetic acid and water, commonly used in cooking and cleaning.

Chemical Properties

Characteristics of a substance that become evident during a chemical reaction.

Composition

The types and amounts of elements or compounds that make up a substance.