Coarse dispersion systems – with a particle size exceeding 100 nm. They are heterogeneous in nature and easily destroyed. The separation of particles is done by using filter paper, this is because of their size. Compared to this, particles under a microscope can be easily observed.
Colloidal-dispersed systems are particle sizes below 100 nm. They are Microheterogeneous Systems. because of their size, the particles pass through the paper filter. They are observed under an ultramicroscope or by reflecting light through the so-called Tyndall effect phenomenon. Colloidal dispersion systems are of great importance and are studied separately as a material.
True solutions have a particle size of less than 1 nm. These are called true solutions or only solutions. They are stable and homogeneous systems (uniform in composition). True solutions are not considered below the level of dispersion systems. Colloidal dispersion systems are of great importance and are studied separately as a material.
Solvent and Solute Examples.
“Solvent and solute examples” Solutes that have a non-uniform composition are called heterogeneous. Their dispersed phase and dispersed medium are in a different aggregate state. There are divisions between the different phases called phase boundaries. Inhomogeneous systems, there is only one phase. This applies only to one substance or to a mixture of substances. This is also the case for solutions. Inhomogeneous mixtures, when the mixture is in a solid-state, then it is referred to as solid solutions when the mixture is in liquid- to liquid, gaseous solutions are called gas mixtures. In liquid solutions, there are two components, namely solvent, and solute. The solvent is a liquid, and the solute may be gas, liquid or solid. If there are two liquids and both phases are liquid, then the larger liquid is defined as the solvent.
Examples that can be given are:
The atmosphere – the solvent is gas and the solute is gas;
Fizzy drinks – solvent is liquid, the solute is gas;
Alcohol in water – solvent is liquid, the solute is liquid;
Cosmetic creams – solvent is solid, the solute is liquid; sugar syrup solvent is a liquid, the solute is in a solid-state;
Metal alloys – solvent is solid and solute is solid;
Sugar syrup solvent is a liquid, the solute is in a solid-state;
The dispersed-dispersed substance is called the dispersed phase. The particles may be gas, solid, or liquid. The particles of the substance are distributed in the dispersed medium. The dispersed medium can also be gas, liquid, or solid. The classification of dispersed systems can be based on various features:
According to particle size;
On the aggregate states of the two phases ;
On the aggregate state of the dispersed medium and of the system as a whole;
“Solvent definition” A substance that has the ability to dissolve substances that are different in aggregate.
Organic solvents are of three main types:
Oxidized (oxygen-containing) alcohols
, glycol ethers, esters; hydrocarbon solvents such as aliphatic, aromatic hydrocarbons;
Halogen solvents containing halogen compounds, such as chlorine, bromine, or iodine.
Тhe solvent molecules and then the particles of the two substances interact and form solvates. If the solvent is water, hydrates are formed and the process becomes hydration. This process is exothermic. Due to diffusion, the solvates are distributed unevenly and energy is lost. Dissolution may be by heat release when the energy of the rupture of the intermolecular bonds is low or the hydration energy is high.
Solids dissolution is in most cases an endothermic process due to the breaking of the crystal lattice. Gases and most solids can be dissolved to a certain extent in a liquid.
In relation to the solubility of the dispersed phase and the equilibrium in the dissolution process, the solutions are: unsaturated, saturated, or saturated. A solution that is in equilibrium with a dissolved and undissolved substance is called saturated. If there is no equilibrium still in the solution, which means that the number of undissolved particles is in greater quantity, the solution is called unsaturated.
If the equilibrium is in the direction of the right reaction, the amount of solute in the system will be greater, then the solution is placed. This type of solution is an unstable system that gradually becomes a saturated type of stability. Dissolution processes can be reversible, which means the chemical equilibrium principle is applied, but they can also be irreversible.
The solution, which contains a large amount of the dissolved substance is called concentrated and, in the opposite case, diluted. Dissolution is a spontaneous physicochemical process. The thermal effects of dissolution are on whether the solid has a crystal lattice and energy is required an endothermic effect, or a hydration or solvation process is carried out where the thermal effect is exothermic. Dissolution is usually a reversible process. Dilution is the direct reaction and crystallization is the reverse. The dissolution of a solid is a reversible process.
Factors that influence the dissolution process are physical properties called the nature of substances
Author: Nidelina Petkova