WHAT ARE THE QUALITATIVE PROPERTIES OF MATTER? - SCIENCE - 2025

The qualitative properties of matter are those that cannot be expressed in numerical values ​​or quantities. They are detected, in many cases, through the senses, since they do not measure them. Our senses can compare these properties, but cannot quantify them.

Because they are perceived through the sense organs, the qualitative properties are called organoleptic properties. Among these properties are: taste, smell, color, malleability, ductility, texture, brittleness, luster, state, magnetism, etc.

On the contrary, the quantitative properties of matter are those that can be expressed in numerical values, obtained through the use of measuring equipment. Examples of these are: boiling point, solubility, refractive index, etc.

Some properties of matter have characteristics that make it difficult to classify them as qualitative or quantitative; such is the case of hardness. As the expression of its value is difficult, it could be classified as qualitative.

However, the Mohs hardness scale, which was constructed based on the ability of one mineral to scratch another, could be a quantitative expression of hardness.

Qualitative properties of matter and its characteristics

Taste

There are four basic flavors of different substances: bitter, sweet, sour and salty, detected by specialized neural structures called taste buds. There are specialized papillae for detecting each of the flavors. Taste is a chemical sense.

Examples of bitter flavors are coffee and beer; lemon juice and vinegar with acidic flavors; candy and in general, sugary foods with sweet flavors; and salty flavors pickles, salted cod, etc.

Color

Colors can be used as qualitative variables. Source: pixabay.com

Substances can have different colors that correspond to wavelengths in the visible light region of the electromagnetic spectrum. The colors are detected thanks to the cones, specialized receptors for the detection of the color of the optic retina.

There are specialized cones for the detection of three colors: blue, green and red. The light emitted by a substance stimulates a group of cones and thus it is perceived that the sea is blue, the blood is red, the sun is yellow, the milk is white, etc.

Odor

The aroma of a coffee is one of the most beloved examples of a qualitative property. Source: Pexels.

Substances emit vapors that carry a small number of their molecules, which are carried through the air to the nostrils. There they interact with specialized cells to capture olfactory stimuli that then transmit the information to the olfactory bulb and from there to the brain.

It is noted that there are 10 main scents, among which are: fruity (apple and pear), floral and perfumes (rose and daisy), sweet (caramel and chocolate), citric (lemon and orange), woody or resinous (pine and eucalyptus) and rotten (carbon sulfide and decaying meat).

Gloss

It is the sensation produced by the interaction of light with a surface of an object, mineral or substance that produces its reflection. Luster is considered as a synonym for brilliance or brilliance. There are three types of luster: metallic, non-metallic, and sub-metallic.

The metallic shine is observed in opaque bodies, that is, they do not let light pass through, for example: copper and aluminum.

Non-metallic is observed in transparent or translucent substances. There are several subtypes, among which are: the adamantine (diamond) and the pearly or iridescent (the mica).

Submetallic are opaque substances that when separated into thin sheets are transparent (gelatin sheets).

Texture

It is defined as the tactile sensation produced by rubbing with the surface of a certain matter. Of course, this is an activity carried out by the sense of touch, through receptors located in the skin that can identify characteristics such as: softness, hardness, roughness and homogeneity.

Tactile softness is the sensation experienced when brushing against the fur of some animals. Hardness is the rubbing sensation of a piece of steel. Roughness is the sensation when touching the surface of a pineapple or the skin of some reptiles.

The homogeneity in the sensation is to travel with the hand a smooth surface, such as that of the bulb of a light bulb or that of a shell.

Ductility

Copper wires

It is the property of certain materials to be able to be subjected to stretching, until obtaining filaments and wires of small diameter; such is the case of copper and aluminum.

Malleability

Aluminum is a malleable material.

Some materials withstand being subjected to strong blows until they become sheets, without experiencing changes in their properties. In some cases, the sheets may be so small that they can be used as wrappers; for example, copper sheets.

Physical state

Matter can be in solid, liquid, gas and plasma states. The solid state is characterized by having its own definite shape. There is a strong interaction between the atoms or the molecules that make it up, which limits their movement.

Liquids have the ability to flow and assume the shape of the container that contains them, their volume is influenced by temperature.

While gases are made up of particles that move at high speed and do not interact with each other. The only limitation to its expansion is to be contained in a container. Plasma is a gaseous state made up of ions and electrons.

All physical states can be directly perceived with the sense of sight, touch, and smell.

Magnetism

The beautiful colors of the Northern Lights are due to cosmic particles emitting energy as they are deflected by the Earth's magnetic field. Source: Pixabay.

It is a force of attraction or repulsion that acts on a material due to the magnetic field produced by the existence of a magnetic dipole or an electric current.

Magnetic materials, among others, are the following: diamagnetic, paramagnetic, ferromagnetic and antiferromagnetic.

Diamagnetics are weakly magnetic materials and are repelled by a magnetic bar, for example: silver and bismuth. Paramagnetics have significant magnetism and are repelled by a magnetic bar; for example, aluminum and palladium.

Ferromagnetics are the quintessential magnetic materials, which is why they are strongly attracted by a magnetic bar; for example, iron and cobalt. And antiferromagnetic ones are non-magnetic, even when they are under the action of a magnetic field; for example, manganese oxide.

Behavior in light

Materials can be opaque, transparent, or translucent. Opaque are materials that do not let light pass through them; like our skin. Transparent materials let light through and objects can be seen clearly through them; just like water and glass.

Translucent materials let light through, but objects cannot be seen clearly through these materials. Objects appear distorted or blurred: oil and frosted glass.

Themes of interest

General properties.

Extensive properties.

Intensive properties.

References

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