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Do all substances dissolve? - Coggle Diagram
Do all substances dissolve?
Definition
What is a substance?
All matter can be considered a substance
What is the solute (the substance)?
What is Matter?
Anything that has mass and takes up volume
What is dissolving?
Dissolving happens when the solvent and solute have strong enough attraction are strong enough to overcome the strenth of the bonds of the solute.
What is the solvent?
State of matter
Liquid
Polarity
Polarity largely determines whether a substance is soluable, like substances dissolve, polar substances dissove in polar solvents since they attract each other, and mis together, same for non polar substances.
Solid
It is possible to have a solid solvent, as solids can still bond with other substances to create a solution. For example, alloys. Alloys are uniform, since they attracted each other when molten.
Gas
Gases technically can be solvents, since dissolving means substances having strong enough attraction between them to overcome the strength of the bonds in itself, so mixing gases would count.
Supercritical fluid
A supercritical fluid is any substance that is inbetween the liquid and gaseous state due to pressure, however not enough pressure to compress it into a solid.
Do strong solvents count?
Things like wood have complex structures and are almst impossible to dissolve. However, very strong solvents such as stong acids can "dissolve" substances such as wood. But these acids don't dissolve things by bonding with them, instead, they destroy the stucture of the substance, can this be still considered as dissolving?
Factors
Solubility
Soluable
Ionic compounds
Ionic compounds have full charges, this makes them more "polar" than the partial charges covalent bonds have, this makes them usually very easy to dissolve in polar solutes such as water
Insoluable
Metals
Metals are here, but there is a tier above this, as metals can be very soluable in the correct solvent, most commonly acids, for example gold in "aqua regia".
Partially soluable
Some Compunds
Some ionic or other compounds are only partially soluble, this is usually when substances require long amounts of time to dissolve.
Very Insoluable
Complex structures
Substances like wood have very complex structues, which are almost impossible to dissolve unless the structure is broken.
All facotrs relating to the solubility of the solute can be controlled by using the same solute.
If there is a solute that does not dissolve, then not all substances will dissolve
Bonds
Ionic
Ionic bonds involve full charges which are more "polar" than all covalend bonds. Therefore, they technically have the strongest dipole bonds, forming lattices
This also causes them to often be very soluable in polar olvents such as water.
Covalent
Covalent bonds can be polar or non polar, thus having different secondary bonds
Like substances dissolve, therefore different covalent bonds can dissolve in different solvents, so multiple solvents may need to be tested.
Metallic
Metallic bonds form lattices with a free flowing "sea of electrons", metallic substances usually require special solvents to dissolve
Structure
Lattice
Lattices are very common, and since covalent, ionic, and metallic lattices are primary bonds rather than secondary bonds, they will be much harder to break or overcome the force of attraction.
Molecule
Molecules' force of attraction are often easier to overcome, as they rely on secondary bonding such as dipole-dipole or dispersion forces.
Surface Area
The surface area of the solute can change how quickly the substance dissolves, as if the solute has larger surfact area, there will be more contact between the solute and the solvent
Temperature
The increase in temperature can increase solubility, increased temperature results in more kinetic energy in the solvent. Molecules with greater kinetic energy can move quickly, thus resulting in the bonds between the molecules being easier to break.
This can be controlled by having all solutes and solvents being at the same temperature, which can be kept constant at room temperature.
Pressure
Pressure has little effect on the solubility of solids and liquids, however can affect the solubility of gases.
Saturation
There is a limited amount of solutes that a set amount of solvent can dissolve, once that amount is reached, the solvent is saturated and cannot dissolve any more solutes.
This can be kept controlled by starting with distilled water, or pure samples of solvents.
Variables
Controlled
The solute
All factors other than the IV should be controlled
Independent
What solvent is used
Different solvents can dissolve different solutes, testing different solvents with the same solute can increase the chance that the solute will dissolve in a solvent.
Dependent
Whether, or how much the substance dissolves.
If the wood dissolves, slightly or completely, it means that a hard-to-dissolve substance is still dissolvable, meaning that others likely will be able to as well. If wood doesn't dissolve, it means that either wood doesn't dissolve entirely, or the experiment is lacking equipment for.
Extraneous
Limitations
Solute
State of matter
Gas
No way to easily contain gases or measure whether the substance has "dissolved"
Supercritical fluids
Impossible to reach the pressure required for supercritical fluids with avaliable equipment
Solids
Impossible to melt most solids with avaliable equipment.
Liquids
Impossible to obtain a large vareity of liquids for testing with avaliable rescources.
Solvent
Obtainability
It is extremely difficult to test the theory that "All" substances dissolve using a practical, since it wuold be near impossible to obtain all substances, and test them in every solution that may dissolve them.
This would be much more praftical as a theoretical investigation, using what is already known about dissolving, and theorising whether all substances will dissolve or not.