Matter

Matter and Its Properties

Matter is anything that has mass, occupies space, and consists of particles. This definition, which may seem complex at first, becomes clearer when the fundamental concepts are explained.

Examples of Matter: Air, Iron, Water, Oxygen, Wood, Gold, Copper, Stone, Soil
Non-Matter: Light, Sound, Energy, Shadow, Wind, Heat, Temperature, Time

Mass

Mass refers to the total amount of matter present in an object. It is a fundamental property of matter and is unique to each substance. Mass is represented by the symbol “m” and is measured using a balance scale. Its unit is gram (g) and its multiples.

Volume

Volume is the amount of space that matter occupies. It is represented by the symbol “V”, and the volume of geometric objects is calculated using geometric formulas, while the volume of liquids and irregular objects is measured using a graduated cylinder. The unit of volume is liters (L) or cubic centimeters (cm³).

Inertia and Particles

Inertia is the resistance of matter to changes in its position. It reflects matter’s tendency to maintain its state of motion or rest. All matter consists of atoms, molecules, or ions. Atoms are the fundamental building blocks of matter, and molecules are formed by the chemical bonding of two or more atoms. Ions are atoms or molecules that carry an electrical charge.

Structure with Gaps

Since matter is made up of particles, there are small gaps between these particles. These gaps exist between atoms as well as subatomic particles.

Object

An object is the form that matter takes. For example, while gold is a substance, a gold ring is an object.

Physical and Chemical Properties

Physical Properties

Physical properties are characteristics of matter that are related to its appearance and physical changes. These can be detected through our five senses or measured directly, such as color, odor, density, melting point, and boiling point.

Chemical Properties

Chemical properties are the ability of matter to undergo chemical changes and form new substances when reacting with other substances or energy. Chemical changes result in alterations to the molecular structure of the substance.

Physical properties are divided into two categories:

Extensive Properties: These depend on the amount of matter (e.g., weight and volume). For example, a pile of salt and a single grain of salt have different masses but the same density.
Intensive Properties: These do not depend on the amount of matter (e.g., density, boiling point, brittleness).

Important Physical Properties

Melting and Freezing Points
- Melting Point: The temperature at which a solid turns into a liquid. For example, the melting point of water is 0°C.
- Freezing Point: The temperature at which a liquid turns into a solid. The freezing point of water is also 0°C.
Boiling Point: The temperature at which a liquid turns into a gas. For example, water boils at 100°C at sea level.
Specific Heat: The amount of heat required to raise the temperature of one kilogram of a substance by one degree Celsius. Different substances have different specific heats, which affect how quickly they heat up.
Solubility: The capacity of a substance to dissolve in another substance. For example, the amount of salt that can dissolve in 100 grams of water at 20°C is its solubility.
Expansion: The process by which a substance’s volume increases as its temperature increases. This happens because molecules move faster and spread out as temperature rises.
Elasticity: The ability of a substance to return to its original shape after being deformed. Rubber is an example of an elastic material.
Conductivity: The ability of a substance to conduct heat or electricity. Metals, for instance, are good conductors of both heat and electricity.
Density: The amount of mass per unit volume of a substance. It indicates how tightly packed the particles of a substance are.

Physical and Chemical Changes

Physical Change: A change in which the structure of the particles of matter does not change. Examples include changes in state (from solid to liquid, liquid to gas). In a physical change, there are no changes to the molecular structure; only the energy or arrangement of the particles changes.
Chemical Change: A change in which the structure of the matter’s particles is altered, leading to the formation of a new substance. Examples include burning wood, the explosion of dynamite when heated, rusting iron, electrolysis, leaf yellowing, and acid-base reactions.

Chemical Changes (Reactions)

Chemical changes are often called “Chemical Reactions”. During a chemical reaction, the initial substances are called reactants, and the substances formed as a result of the reaction are called products.

Exothermic and Endothermic Reactions

Exothermic Reactions: Reactions that release heat to the surroundings. These reactions generally release energy. For example, combustion reactions are exothermic.
Endothermic Reactions: Reactions that absorb heat from the surroundings. Energy (heat) is taken from the environment. Decomposition reactions are examples of endothermic reactions.

Classification of Matter

Solid Matter (s)

Properties:

Contains a single type of particle.
Melting and boiling points are fixed.
Homogeneous.
Can be divided into elements and compounds.
Cannot be separated into simpler substances by physical methods.
Has a definite mass, volume, and shape.

Liquid Matter (l)

Has a definite mass and volume.
Shape changes to take the shape of the container.

Gas Matter (g)

Has a definite mass.
Fills the container and takes its shape and volume.

Pure Substances and Mixtures

Pure Substances: Substances that have a specific and constant composition and distinct properties.
Mixtures: Combinations of two or more pure substances. Mixtures can be classified as homogeneous or heterogeneous depending on the uniformity of their composition.

Homogeneous Mixtures: Mixtures that have a uniform composition throughout. Examples include sugar water, salt water, and aluminum alloys.

Heterogeneous Mixtures: Mixtures where the composition is not uniform. Different phases may be visible. Examples include cement, muddy water.

Properties of Mixtures:

Mixtures do not have fixed melting and boiling points.
Examples of mixtures include salt water, tea, coffee, and soil.

Homogeneous Mixtures:

Alloys and solutions are homogeneous mixtures. A solution is formed when a solute and a solvent combine. Solutions can be of the following types:

Liquid-liquid
Solid-liquid
Solid-solid
Liquid-gas
Gas-gas

Examples:

Cologne (alcohol-water-fragrance)
Sugar water, salt water
Steel (iron-carbon alloy)
Brass (copper-zinc alloy)
Carbonated drinks
Air

Heterogeneous Mixtures:

Heterogeneous mixtures are those that do not have the same composition throughout and can contain different phases.

Suspension: A liquid-solid heterogeneous mixture. Examples: water and sand, ayran.

Emulsion: A liquid-liquid heterogeneous mixture. Examples: water and olive oil, water and gasoline.

Aerosols (Heterogeneous Mixtures)

An aerosol is the dispersion of a solid or liquid in a gas.