Question

Define the following terms: solid, liquid, gas, pure substance, element, compound, homogeneous mixture, heterogeneous mixture, solution, chemical change, physical change.

Short answer

Solid: State of matter with definite shape and volume; particles closely packed and limited movement. Examples: ice, wood, metal. Liquid: State of matter with definite volume but no definite shape; particles less closely packed, allowing flow. Examples: water, oil, blood. Gas: State of matter with no definite shape or volume; particles more spaced out, allowing expansion and compression. Examples: air, hydrogen, oxygen. Pure Substance: Matter with consistent composition and properties; can be an element or compound. Examples: water, gold. Element: Pure substance that cannot be broken down chemically; made of one type of atom. Examples: carbon, oxygen, hydrogen. Compound: Pure substance formed from two or more elements chemically combined; fixed ratio. Examples: water (H2O), carbon dioxide (CO2), table salt (NaCl). Homogeneous Mixture: Substances uniformly mixed and have consistent composition. Examples: air, sugar dissolved in water. Heterogeneous Mixture: Substances not uniformly mixed, different compositions in different parts. Examples: sand and water, oil and water, mixed nuts. Solution: Homogeneous mixture where solute is dissolved in solvent. Examples: saltwater. Chemical Change: Process transforming substances into new substances with different properties; involves rearrangement of atoms/molecules. Examples: burning wood, photosynthesis, rusting iron. Physical Change: Process altering physical properties without changing chemical composition. Examples: melting ice, breaking glass, inflating balloon.

Step-by-step solution

Solid

A solid is a state of matter characterized by its definite shape and volume. The particles in a solid are closely packed together and have limited movement, resulting in a well-defined structure. Examples of solids include ice, wood, and metal.

Liquid

A liquid is a state of matter that takes the shape of its container and has a definite volume but no definite shape. The particles in a liquid are less closely packed than in a solid, allowing the liquid to flow. Examples of liquids include water, oil, and blood.

Gas

A gas is a state of matter that has no definite shape or volume, assuming the shape and volume of its container. The particles in a gas are more spaced out than in solids and liquids, allowing the gas to expand and compress easily. Examples of gases include air, hydrogen, and oxygen.

Pure Substance

A pure substance is a form of matter that has a consistent composition and properties throughout. It can be either an element or a compound. Examples of pure substances include water (a compound) and gold (an element).

Element

An element is a pure substance that cannot be broken down into simpler substances by chemical means. Elements are made up of one type of atom, with each element having its unique atomic number. Examples of elements include carbon, oxygen, and hydrogen.

Compound

A compound is a pure substance formed by the chemical combination of two or more elements in a fixed ratio. Compounds can only be separated by chemical means. Examples of compounds include water (H2O), carbon dioxide (CO2), and table salt (NaCl).

Homogeneous Mixture

A homogeneous mixture is a combination of substances that are uniformly mixed and have a consistent composition throughout. The different components of a homogeneous mixture cannot be seen individually. Examples of homogeneous mixtures include air (a mixture of gases) and sugar dissolved in water (a solution).

Heterogeneous Mixture

A heterogeneous mixture is a combination of substances that are not uniformly mixed and have different compositions in different parts of the mixture. The individual components can typically be visually distinguished. Examples of heterogeneous mixtures include sand and water, oil and water, and a bowl of mixed nuts.

Solution

A solution is a type of homogeneous mixture where one substance (the solute) is dissolved in another substance (the solvent). Solutions can be in the solid, liquid, or gaseous state, but the most common example is a liquid solution like saltwater.

Chemical Change

A chemical change is a process in which one or more substances are transformed into new substances with different properties. This change occurs at the molecular level and involves a rearrangement of atoms or molecules. Examples of chemical changes include burning wood, photosynthesis, and the rusting of iron.

Physical Change

A physical change is a process that alters the physical properties of a substance, such as its shape, size, or state (solid, liquid, or gas), without changing its chemical composition. The molecules or atoms of the substance remain unchanged. Examples of physical changes include melting ice, breaking a glass, and inflating a balloon.