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can still dissolve more salt. But after adding some spoons of salt, there
comes a point when salt stops dissolving and the extra salt settles at the

bottom. This means the water has reached its limit for dissolving salt and is
now called a saturated solution at that temperature. In a saturated solution,
no more solute can dissolve unless the temperature changes. So, an

Unsaturated solution unsaturated solution can dissolve more solute, while a saturated solution
cannot dissolve anymore and has leftover undissolved solute.
Concentration is the amount of solute (the substance dissolved) present in

a fixed quantity of a solution or solvent. Depending on how much solute is
dissolved, a solution can be called dilute if it has less solute, or concentrated
Solution
if it has more solute. These terms are relative, meaning what is considered
dilute or concentrated depends on the amount of solute compared to the
Undissolved
salt
solvent. For example, if a little sugar is dissolved in water, it forms a dilute
Saturated solution
solution, but if a lot of sugar is dissolved, the solution is concentrated.
Science Concentration helps us understand how strong or weak a solution is based
Bytes
on the amount of solute it contains.

Testimony So, one can say that, the solution obtained by dissolving one spoon of salt is
The Dead Sea has one of
the highest salt dilute as compared to that obtained by dissolving two or more spoons of
concentra ons on Earth. salt. Can you now reflect — which solution is more concentrated; 2 spoons
its water is so dense that
people can easily float on of salt in 100 mL of water or 4 spoons of salt in 50 mL of water? We can say
it without sinking. that the maximum amount of solute that dissolves in a fixed quantity of the
solvent is called its solubility .

Does temperature affect the solubility of a solute? Let us find out!

HOW DOES TEMPERATURE AFFECT THE SOLUBILITY OF A
Laboratory stand
SOLUTE?
When you take about 50 mL of water at room temperature
Laboratory (around 20 °C) and add baking soda (sodium hydrogen
thermometer
carbonate) while stirring, the baking soda dissolves until no
Glass rod
more can dissolve, leaving some solid at the bottom. If you
Beaker
Water heat the water to 50 °C and continue stirring, the solid
containing
baking soda baking soda that was left undissolved will dissolve. Heating

Wire gauze the water increases its ability to dissolve more baking soda.
Tripod stand When the temperature is raised even higher to 70 °C, even
more baking soda dissolves before any solid remains. This
Spirit lamp
shows that the solubility of baking soda in water increases as
the temperature rises. In simple terms, warmer water can
Dissolution of baking soda in water dissolve more baking soda than cooler water.

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