Difference Between

Difference Between Saturated Solution and Unsaturated Solution

Nex Virox Team
Written byNex Virox Team
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Varshal Nirbhavane
Senior SEO & Organic Growth Professional · 5+ years
19 min read
Quick answer

The main difference between Saturated Solution and Unsaturated Solution is that a saturated solution holds the maximum possible dissolved solute at a given temperature, while an unsaturated solution can still dissolve more solute. Saturated Solution is one where no more solute dissolves, while Unsaturated Solution is one that can dissolve additional solute.

Key takeaways

  • Core distinction: A saturated solution holds maximum dissolved solute at given temperature, while unsaturated holds less.
  • How each works: Saturated solutions maintain dynamic equilibrium between dissolved and undissolved solute particles, but unsaturated solutions do not.
  • Detection method: Adding more solute to saturated solution leaves undissolved crystals; unsaturated solution dissolves added solute completely.
  • Best-fit use case: Saturated solutions suit crystallization and precise concentration control; unsaturated solutions suit reactions needing more dissolving capacity.
  • Common decision mistake: Assuming saturation is fixed ignores temperature changes; heating converts saturated solutions into unsaturated ones.

Difference Between Saturated Solution and Unsaturated Solution: Comparison Table

AspectSaturated SolutionUnsaturated Solution
DefinitionHolds the maximum solute that a solvent can dissolve at a given temperature.Contains less solute than the solvent can theoretically hold at that temperature.
Core MechanismDissolution rate equals crystallization rate, creating a dynamic equilibrium between phases.Dissolution continues because the solute concentration stays below the solubility limit.
Solubility LimitSolute concentration sits exactly at the saturation point, matching the solubility curve.Solute concentration sits measurably below the solubility curve for that temperature.
Dissolution CapacityCannot dissolve additional solute; added solute settles at the container bottom.Has remaining capacity to dissolve more solute until reaching the saturation threshold.
Equilibrium StateReaches a stable equilibrium where no net change in dissolved solute occurs.Remains in a non-equilibrium state with a net transfer of solute into solution.
Temperature DependenceSaturation point shifts with temperature; most solids become more soluble when heated.Can become saturated if temperature drops, reducing the solvent's holding capacity.
Visible ParticlesUndissolved solute crystals remain visible at the bottom of the container.Appears clear with no visible undissolved solute particles present in the mixture.
Crystal FormationAdding a seed crystal triggers immediate crystallization of excess dissolved solute.Adding a seed crystal dissolves completely without triggering any crystal precipitation.
Concentration LevelRepresents the highest possible concentration achievable at a fixed temperature.Holds a concentration value that is always lower than the maximum possible.
Addition of SoluteAdded solute remains undissolved, accumulating as a solid layer at the bottom.Added solute dissolves readily until the solution approaches its saturation point.
Evaporation EffectEvaporating solvent causes dissolved solute to precipitate out as solid crystals.Evaporation concentrates the solution, eventually converting it into a saturated state.
Supersaturation PotentialCan become supersaturated only through careful cooling or slow evaporation techniques.Cannot become supersaturated without first passing through the saturated state.
Stirring ImpactStirring speeds up equilibrium but does not increase the total dissolved amount.Stirring accelerates dissolution by exposing fresh solvent to undissolved solute.
Preparation MethodRequires adding solute until excess remains undissolved after prolonged stirring.Requires adding less solute than the known solubility value for that temperature.
Filtration ResultFiltering removes excess solid, leaving a saturated filtrate at equilibrium.Filtering removes nothing because no undissolved solid exists in the mixture.
Concentration UnitsExpressed as molarity or molality at the solubility limit, such as 5.5 mol/L.Expressed as molarity below the limit, for example 2.0 mol/L at same temperature.
Solution StabilityRemains stable indefinitely as long as temperature and pressure stay constant.Stable until solute is added or temperature changes alter the solubility balance.
ReversibilityCan revert to unsaturated by heating the solution to raise its solubility.Can become saturated by cooling or by adding more solute to the mixture.
Industrial UseUsed in crystallization processes to purify compounds like salt or sugar.Used in reactions needing controlled, incomplete dissolution of a reactant.
Laboratory RoleServes as a reference point for determining solubility constants of compounds.Serves as a working solution for titrations and dilution-based experiments.
Pharmaceutical RoleUsed to create saturated drug solutions for maximum dose delivery per volume.Used for lower-dose formulations requiring precise, sub-saturation drug concentrations.
Food ApplicationProduces sugar syrups for candies where maximum sweetness is required.Produces beverages and broths where moderate solute levels maintain palatability.
Measurement DifficultyConcentration is fixed by temperature, making measurement straightforward and reproducible.Concentration varies by preparation, requiring analytical measurement for exact values.
Response to CoolingCools to precipitate excess solute, forming crystals until equilibrium re-establishes.Cools without precipitating until the new lower solubility limit is reached.
Response to HeatingHeating allows more solute to dissolve, shifting equilibrium to a higher limit.Heating increases capacity further, widening the gap below the new saturation point.
Pressure SensitivityAffected by pressure mainly for gas solutes, where higher pressure raises solubility.Gas solutes dissolve more readily under pressure, moving toward saturation faster.
Common ExamplesSeawater with undissolved salt at its floor or sugar water with settled sugar.Tap water with dissolved minerals or a pinch of salt in a glass of water.
Typical UsersChemical engineers and crystallographers working on separation and purification processes.Lab technicians and students preparing reagents for routine analytical experiments.
Key LimitationCannot dissolve more solute, limiting concentration for reactions needing higher loads.Offers lower concentration, requiring larger volumes for equivalent solute amounts.
Best-Fit ScenarioIdeal for crystallization, recrystallization, and maximum-concentration delivery systems.Ideal for gradual dissolution, controlled dosing, and temperature-sensitive reactions.

What Is Saturated Solution?

Saturated Solution holds the maximum amount of dissolved solute that a solvent can accept at a given temperature. It exists at a dynamic equilibrium where dissolved particles return to solid form at the same rate they dissolve. This state defines the upper limit of solubility.

Definition of Saturated Solution

A saturated solution is a homogeneous mixture in which the dissolved solute concentration equals the maximum solubility limit for that specific solvent at a fixed temperature and pressure. Adding more solute will not dissolve; instead, it remains as a visible solid precipitate at the bottom of the container.

Key Characteristics of Saturated Solution

CharacteristicWhat It Means in Practice
Maximum solute loadThe solvent holds every solute particle it can possibly dissolve at that exact temperature.
Dynamic equilibriumDissolving and crystallising happen at equal speeds, keeping the dissolved amount perfectly constant.
Temperature dependentHeating usually allows more solute to dissolve; cooling forces excess solute to precipitate out.
Visible undissolved soluteExtra crystals or powder sit at the bottom, proving the saturation point has been reached.
Fixed concentrationThe solute-to-solvent ratio stays identical as long as temperature and pressure remain unchanged.
Precipitation on coolingLowering the temperature makes the solution deposit crystals because solubility drops sharply.
Seed crystal triggerA tiny crystal dropped in can instantly cause rapid crystallisation of the entire dissolved excess.
Recrystallisation basisPurification methods rely on this state to grow pure solid crystals from impure mixtures.
Solubility curve pointEvery saturated solution corresponds to a single precise point on the substance's solubility curve.
Pressure sensitive for gasesCarbonated drinks are saturated with gas under high pressure; opening the bottle releases it.

Common Examples of Saturated Solution

  • Saltwater in a brine tank – water holds all the salt it can; leftover salt stays undissolved on the bottom.
  • Sugar in cold tea – cold liquid dissolves limited sugar, leaving a visible layer of crystals at the glass base.
  • Carbonated soda – carbon dioxide gas saturates the liquid under sealed high pressure inside the bottle.
  • Seawater with evaporating pools – solar evaporation concentrates salts until the water reaches its saturation limit.
  • Rock candy growth – a supersaturated sugar solution cools and deposits crystals onto a suspended string.
  • Soil groundwater with calcium – underground water holds dissolved calcium until it saturates and forms limestone deposits.
  • Battery electrolyte – lead-acid batteries use a saturated sulfuric acid solution to maintain stable voltage output.
  • Kombucha fermentation – dissolved sugars reach saturation, limiting further dissolution as yeast consumes them.
  • Hot springs mineral water – dissolved silica saturates the water and precipitates as geyserite around vents.
  • Fruit juice concentrate – manufacturers saturate water with fruit sugars to create shelf-stable syrups.

Advantages and Limitations of Saturated Solution

AdvantagesLimitations
Enables precise crystal purification in laboratories and industrial chemical processing.Becomes unstable with any temperature shift, causing unwanted precipitation and clogging equipment.
Provides a reliable standard for measuring exact solubility values of different substances.Requires constant temperature control, which consumes significant energy in large-scale manufacturing.
Supports controlled crystallisation to produce uniform particle sizes in pharmaceutical drug production.Cannot dissolve additional reactants, limiting reaction rates in industrial chemical synthesis processes.
Offers a stable concentration reference for calibrating analytical chemistry instruments.Undissolved solids interfere with accurate volume measurements and create handling difficulties in pipes.
Enables food preservation techniques like brining and sugaring that inhibit microbial growth.Prone to supersaturation, which causes sudden explosive crystallisation when disturbed or seeded.
Allows predictable separation of dissolved solids from liquids through controlled evaporation methods.Highly sensitive to impurities that alter the actual saturation point unpredictably during processing.
Creates consistent electrolyte conditions needed for reliable battery and electrochemical cell performance.Corrosive saturated salt solutions accelerate metal degradation and damage storage containers over time.
Provides a natural geological mechanism for forming mineral deposits and cave structures over centuries.Difficult to transport because temperature drops during transit cause solid blockages in pipelines.
Supports density-based separation techniques used in mineral processing and ore refinement.Limited capacity means large volumes of solvent are wasted when trying to dissolve more solute.
Enables supersaturation techniques for creating specialised materials like synthetic gems and optical crystals.Reaching saturation can take hours of stirring, making batch production slow and inefficient.

What Is Unsaturated Solution?

Unsaturated Solution is a liquid mixture that holds less dissolved solute than its maximum capacity at a given temperature. It can dissolve additional solute if more is added. This state exists because the solvent has not yet reached its solubility limit, leaving room for further dissolution.

Definition of Unsaturated Solution

Unsaturated Solution is a homogeneous mixture in which the concentration of dissolved solute is lower than the solubility limit of that solute in the solvent at a specific temperature and pressure. Adding more solute to this solution will cause the added substance to dissolve completely until saturation is reached.

Key Characteristics of Unsaturated Solution

CharacteristicWhat It Means in Practice
Dissolves more soluteAdding extra sugar or salt will fully dissolve without settling at the bottom.
Below solubility limitThe solute amount stays under the maximum mass the solvent can hold at that temperature.
Temperature dependentHeating the solution raises capacity, so a warm unsaturated liquid can hold even more solute.
Homogeneous mixtureParticles are evenly distributed, so every sample has identical composition throughout.
No visible residueThe container bottom stays clear with no undissolved crystals or solid particles present.
Stable at restLeaving it undisturbed does not cause solute to precipitate or separate out over time.
Dynamic equilibrium absentDissolution and crystallisation rates are not equal because crystallisation does not occur yet.
More solvent presentThe ratio of solvent to solute is high, keeping particles widely spaced apart.
Reversible stateEvaporating solvent or cooling it can convert this mixture into a saturated one.
Common in daily lifeMost drinks and tap water exist in this state because they rarely reach full capacity.

Common Examples of Unsaturated Solution

  • Sea water – contains dissolved salts but still holds far less than its maximum possible salt load.
  • Sweetened tea – a few teaspoons of sugar dissolve completely, leaving no crystals in the cup.
  • Carbonated soft drink – dissolved carbon dioxide remains below the liquid's full gas capacity.
  • Salt in cold water – a pinch of table salt dissolves fully because cold water holds more capacity.
  • Sugar in lemonade – the sugar content stays under the solubility limit at room temperature.
  • Oxygen in blood – dissolved oxygen in plasma is far below the plasma's maximum gas capacity.
  • Instant coffee – a small spoonful dissolves completely in hot water without any leftover granules.
  • Rainwater – contains trace dissolved gases and minerals but remains well below saturation levels.
  • Dilute hydrochloric acid – hydrogen chloride gas is dissolved at a concentration far under its limit.
  • Fruit juice concentrate – when mixed with water, the sugar and acids stay below their solubility thresholds.

Advantages and Limitations of Unsaturated Solution

AdvantagesLimitations
Easily absorbs more solute, making it flexible for recipes and industrial mixing processes.Cannot deliver maximum solute concentration, so it is inefficient for high-yield crystallisation.
Stable and predictable, so it does not spontaneously deposit solids during storage or transport.Requires careful measurement because adding too much solute suddenly turns it saturated.
Safe for biological systems like blood, where dissolved gases must stay below dangerous thresholds.Weak osmotic pressure makes it ineffective for food preservation or drawing moisture out.
Allows gradual dosing of medication, letting doctors control active ingredient levels precisely.Dilute nature means large volumes are needed to deliver meaningful amounts of active chemicals.
Forms quickly without heating or stirring, saving energy in many manufacturing and lab workflows.Prone to becoming saturated unintentionally when solvent evaporates, causing unexpected precipitation.
Transparent and clear, which aids visual inspection in quality control and laboratory analysis.Limited solute content reduces electrical conductivity compared to concentrated solutions.
Supports plant nutrient uptake because roots absorb minerals more readily from dilute mixtures.Temperature changes can shift it toward saturation, making process control more difficult.
Easy to dilute further, allowing precise adjustment of concentration for sensitive chemical reactions.Holds less buffering capacity, so pH shifts more dramatically when acids or bases are added.
Prevents clogging in pipes and equipment because no crystals form to block narrow channels.Offers slower reaction rates in chemistry because fewer solute particles collide per unit volume.
Common and naturally occurring, so it requires no special preparation for most everyday uses.Cannot be used for supersaturation techniques that rely on unstable, overloaded liquid states.

Similarities Between Saturated Solution and Unsaturated Solution

Shared AspectHow Saturated Solution and Unsaturated Solution Are Alike
Basic CompositionA saturated solution and an unsaturated solution both contain a solute dissolved in a solvent.
Core CategoryBoth a saturated solution and an unsaturated solution are classified as homogeneous mixtures at the molecular level.
Primary ComponentsA saturated solution and an unsaturated solution each require exactly two parts: a solute and a solvent.
Solvent RoleBoth a saturated solution and an unsaturated solution use the solvent as the dissolving medium in greater quantity.
Solute RoleA saturated solution and an unsaturated solution both feature the solute as the substance being dissolved.
Physical StateA saturated solution and an unsaturated solution can both exist as liquids, gases, or solids depending on conditions.
UniformityBoth a saturated solution and an unsaturated solution have identical composition throughout every sample portion.
Particle SizeDissolved particles in a saturated solution and an unsaturated solution are both smaller than one nanometer.
Visual ClarityA saturated solution and an unsaturated solution both appear transparent and clear to the naked eye.
Filtration BehaviorBoth a saturated solution and an unsaturated solution pass completely through filter paper without leaving residue.
Light ScatteringA saturated solution and an unsaturated solution both fail to scatter a beam of light (Tyndall effect absent).
SedimentationNeither a saturated solution nor an unsaturated solution settles out particles when left standing undisturbed.
Separation MethodBoth a saturated solution and an unsaturated solution require evaporation or distillation for solute recovery.
Temperature DependenceSolubility in a saturated solution and an unsaturated solution both change predictably with temperature shifts.
Pressure InfluenceA saturated solution and an unsaturated solution both respond to pressure mainly when gases are dissolved.
ReversibilityBoth a saturated solution and an unsaturated solution can convert into each other by adding or removing solute.
Everyday UseA saturated solution and an unsaturated solution both appear routinely in cooking, cleaning, and laboratory work.
Biological RoleA saturated solution and an unsaturated solution both carry nutrients and waste in living organisms.
Concentration ExpressionBoth a saturated solution and an unsaturated solution can be measured using molarity, molality, or percent composition.
Preparation MethodA saturated solution and an unsaturated solution both start by mixing solute into solvent with stirring.
Equilibrium ConceptBoth a saturated solution and an unsaturated solution involve dynamic exchange at the solute-solvent boundary.
Chemical StabilityA saturated solution and an unsaturated solution both remain chemically stable when stored in sealed containers.
Freezing BehaviorBoth a saturated solution and an unsaturated solution freeze at lower temperatures than the pure solvent alone.
Boiling BehaviorA saturated solution and an unsaturated solution both boil at higher temperatures than the pure solvent.
Osmotic ActivityBoth a saturated solution and an unsaturated solution exert osmotic pressure across semipermeable membranes.
Electrical ConductivityA saturated solution and an unsaturated solution both conduct electricity only when the solute is an electrolyte.
pH MeasurementBoth a saturated solution and an unsaturated solution have their acidity or basicity measured with a pH meter.
Density VariationA saturated solution and an unsaturated solution both show density values different from the pure solvent.
Standard Lab UseBoth a saturated solution and an unsaturated solution serve as standard reagents in titration experiments.
Long-Term StorageA saturated solution and an unsaturated solution both remain usable for months if evaporation is prevented.

Saturated Solution or Unsaturated Solution: Which Should You Choose?

The deciding variable is whether you need maximum dissolved solute or maximum dissolving capacity. Choose Saturated Solution when you require the highest possible concentration at a given temperature. Choose Unsaturated Solution when you need room to dissolve more solute, ensuring stability, accuracy, or complete dissolution without precipitation risk.

When to Use Saturated Solution

Choose Saturated Solution when maximum concentration is your goal, such as creating a recrystallization bath or a standard for solubility testing. It suits processes needing precise equilibrium conditions, like sugar crystallization in candy making, where excess solute guarantees a stable endpoint at a fixed temperature.

When to Use Unsaturated Solution

Choose Unsaturated Solution when you need guaranteed full dissolution or future solute additions, like preparing a nutrient stock for plant growth or a chemical reagent. It is ideal when temperature might drop, preventing unwanted crystallization, or when you require a stable, predictable concentration without the risk of precipitation.

Common Misconceptions About Saturated Solution and Unsaturated Solution

Common MythThe Reality
A saturated solution is always thick, syrupy, or highly viscous.A saturated solution can be as thin as water; saturation refers to dissolved solute concentration, not viscosity or texture.
Stirring or shaking a solution makes it more saturated.Stirring only speeds up dissolving; a saturated solution holds the maximum solute at that temperature, and stirring cannot exceed that limit.
An unsaturated solution contains no solute at all.An unsaturated solution contains some solute, but less than the maximum amount the solvent can dissolve at that temperature.
Heating a saturated solution always causes solute to crystallize out.Heating a saturated solution usually lets it dissolve more solute, turning it unsaturated; cooling, not heating, triggers crystallization.
A saturated solution cannot dissolve any more solute ever.A saturated solution cannot dissolve more solute at that specific temperature; raising the temperature allows additional solute to dissolve.
Unsaturated and saturated solutions look visibly different.Saturated and unsaturated solutions often look identical; only a test with added solute reveals which one you have.
Adding more solvent makes a saturated solution unsaturated automatically.Adding solvent to a saturated solution does create an unsaturated solution, but the original solute remains dissolved and total mass changes.
A saturated solution is always at its boiling point.A saturated solution has no fixed temperature; it can be saturated at 20°C, 80°C, or any temperature where solute stops dissolving.
Once saturated, a solution stays saturated if temperature drops.Cooling a saturated solution often makes it supersaturated or causes excess solute to precipitate out, leaving a saturated or unsaturated state.
Unsaturated solution means the solvent is completely empty of solute.An unsaturated solution contains dissolved solute below its solubility limit; it is not empty, just not at maximum capacity.
Saturated solutions are always darker or more colored than unsaturated ones.Color intensity does not indicate saturation; a saturated colorless salt solution looks identical to an unsaturated one.
Evaporation always turns an unsaturated solution into a saturated one.Evaporation removes solvent, concentrating solute; it can produce a saturated solution, but only if enough solvent leaves and solute remains dissolved.
You can tell saturation by tasting or smelling the solution.Taste and smell cannot measure saturation; only adding solute and observing whether it dissolves confirms a saturated solution's status.
A saturated solution has the highest possible concentration of any solution.A saturated solution has maximum concentration at a given temperature, but a supersaturated solution holds even more solute temporarily.
Unsaturated solutions are always dilute or weak.An unsaturated solution can be concentrated; it is simply below its solubility limit, not necessarily weak or dilute.
Pressure does not affect saturation of liquid solutions.Pressure affects gas solubility in liquids; a saturated solution of gas in liquid changes saturation when pressure changes.
All solids dissolve faster in hot water, so saturation is impossible hot.Most solids dissolve more in hot water, but saturation still occurs; the saturated solution simply holds more solute at higher temperature.
A saturated solution is a pure substance, not a mixture.A saturated solution is a homogeneous mixture of solvent and dissolved solute, not a pure substance by any definition.
If no solid is visible, the solution must be unsaturated.A saturated solution can have no visible solid if all solute dissolved exactly to the limit; undissolved solid is not required for saturation.
Unsaturated solutions cannot be made from a saturated solution.Adding solvent or raising temperature converts a saturated solution into an unsaturated solution, so the change is reversible and common.
Boiling a saturated solution makes it more saturated.Boiling removes solvent, concentrating solute, but it may cause precipitation; saturation depends on remaining solvent volume and temperature.
Saturation is a fixed property of a chemical, like density or melting point.Saturation is conditional, varying with temperature, pressure, and solvent type; it is not an intrinsic constant property of a solute.
An unsaturated solution will become saturated if you wait long enough.Waiting alone does not change concentration; an unsaturated solution stays unsaturated unless solvent evaporates or more solute is added.
Adding any amount of solute to an unsaturated solution makes it saturated.Adding solute only saturates the solution when the added amount reaches the solubility limit; small additions keep it unsaturated.
Saturated solutions are always at room temperature.Saturation occurs at any temperature; a solution saturated at 0°C is still a saturated solution, just at a lower solubility limit.
Unsaturated solution means the solute is not fully dissolved.An unsaturated solution has all solute fully dissolved; it is unsaturated because it could dissolve more, not because solute is undissolved.
You can make a saturated solution by adding solute until it looks cloudy.Cloudiness indicates undissolved solid, not saturation; a saturated solution can be clear, and cloudiness means excess solid, not saturation.
Saturation only applies to solids dissolved in liquids.Saturation applies to gases in liquids, gases in solids, and liquids in liquids; it is not limited to solid-liquid solutions.
A saturated solution has equal amounts of solute and solvent.Saturation does not require equal masses; a saturated solution may have tiny solute or huge solute, depending on solubility limits.
Once saturated, the solution cannot change back to unsaturated.Adding solvent or heating a saturated solution converts it back to an unsaturated solution; the change is fully reversible under new conditions.

Conclusion

Difference Between Saturated Solution and Unsaturated Solution comes down to dissolved solute capacity. A saturated solution holds maximum solute at a given temperature, so added solute settles. An unsaturated solution can dissolve more solute. Pick saturated for maximum concentration; pick unsaturated when you need to dissolve additional solute.

FAQs on Difference Between Saturated Solution and Unsaturated Solution

What is the difference between a saturated solution and an unsaturated solution?
A saturated solution holds the maximum dissolved solute at a given temperature, while an unsaturated solution can still dissolve more solute under the same conditions.
How can you tell if a solution is saturated or unsaturated?
Add a small amount of solute; if it dissolves, the solution is unsaturated, but if it settles at the bottom, the solution is saturated.
Which solution is better for dissolving more sugar, saturated or unsaturated?
An unsaturated solution is better for dissolving more sugar because it has remaining capacity to accept additional solute until it reaches its saturation point.
Does a saturated solution cost more to prepare than an unsaturated solution?
A saturated solution typically costs less to prepare because it requires less solute per unit volume than an unsaturated solution at the same temperature.
Is it safe to drink a saturated solution of salt water?
No, drinking a saturated salt solution is unsafe because its extreme salinity can cause dehydration and harm your kidneys, unlike a dilute unsaturated solution.
Can a saturated solution and an unsaturated solution be mixed together?
Yes, mixing them creates a new solution whose saturation level depends on the combined solute and solvent amounts, which may become saturated or stay unsaturated.
What is a common beginner mistake when making a saturated solution?
A common mistake is heating the solvent and assuming the solution stays saturated at room temperature, but cooling causes excess solute to precipitate out.
Are saturated and unsaturated solutions interchangeable in a chemical reaction?
No, they are not interchangeable because a saturated solution may limit reaction rates by providing less available solute, while an unsaturated solution offers more dissolved reactant.
Why is an unsaturated solution used in making soft drinks?
An unsaturated solution is used in soft drinks to keep carbon dioxide gas dissolved under pressure, preventing premature bubbling and maintaining the drink's fizz.
Can I switch an unsaturated solution to a saturated solution by adding more solute?
Yes, you can switch it by adding more solute and stirring until no more dissolves, which indicates the solution has reached its saturation point.