Saturated and Supersaturated Solutions

Key Questions

• What is a supersaturated solution?

  A supersaturated solution contains more solute at a given temperature than is needed to form a saturated solution.

  Increased temperature usually increases the solubility of solids in liquids.

  For example, the solubility of glucose at 25 °C is 91 g/100 mL of water. The solubility at 50 °C is 244 g/100 mL of water.

  If we add 100 g of glucose to 100 mL water at 25 °C, 91 g dissolve. Nine grams of solid remain on the bottom. We have a saturated solution.

  

  If we now heat the mixture to 50 °C, the remaining 9 g of glucose will dissolve. At the new temperature, the solubility limit in 100 mL of water is 244 g glucose. With only 100 g of glucose dissolved, the solution is now unsaturated.

  If we next cool the mixture back to 25 °C, 9 g of glucose should precipitate from solution.

  If glucose crystals do not form, the system has more dissolved glucose (100 g) than it can hold at 25 °C (91 g). We have a supersaturated solution.

  The first step in the formation of crystals is nucleation. This is when the solute molecules arrange themselves to form crystals.

  Sometimes this happens at once. If it doesn't, we have a supersaturated solution. This is an unstable situation.

  A piece of dust or a small crystal of the solute, a seed crystal, provides a template for crystallization of the excess solute. The excess solute starts to form crystals on the nuclei.

  Once crystals start to form, their surface area increases as they grow. This attracts more molecules and promotes growth at an ever-increasing rate. Finally, the solution stabilizes and no more crystals can form.

  Ernest Z. · 5 · May 24 2014
• What are solubility curves?

  A solubility curve is a data based graph comparing the amount of solute that will dissolve in a given amount of solvent at various temperatures.

  The most typical solubility curves are graphed based solid and gaseous solutes dissolved in 100 grams of water.

  

  
  SMARTERTEACHER YouTube

  BRIAN M. · 1 · Oct 14 2014

• How are saturated solutions at equilibrium?
• How are supersaturated solutions prepared?
• How can you identify a saturated solution?
• How do supersaturated solutions demonstrate conservation of energy?
• How do you make saturated solution of potassium iodide?
• How do you make saturated solution of sodium bicarbonate?
• What is an example of a saturation practice problem?
• What is a saturated solution?
• What is an example of a saturated solution practice problem?
• What are some common mistakes students make with saturated solutions?
• What is a supersaturated solution?
• What is an example of a supersaturated solution practice problem?
• How does pressure affect a saturated solution?
• How can a saturated solution be prepared?
• How can a supersaturated solution be made?
• How can a saturated solution become supersaturated?
• How can I calculate the molarity of a saturated solution?
• How do you calculate the pH of a saturated solution?
• How does the amount of gas in a saturated solution change with pressure?
• How can I make a supersaturated solution crystallize?
• How can I make a saturated solution of potassium iodide?
• How to make a saturated solution of sodium chloride?
• What happens when supersaturated solution cools down?
• Are all supersaturated solutions unstable?
• Why do supersaturated solutions crystallize?
• Why is a saturated salt solution at equilibrium?
• What does the line in a solubility chart mean?
• What are solubility curves?
• Question #5835c
• Question #79d00
• Question #d7a1a
• Question #71458
• Question #4d493
• what type of solution will be created when 35 grams of Nh4Cl is added to 25 ml of water at 80 Celsius?
• Question #deead
• What happens to a saturated solution of sugar in water when the temperature of the solution is suddenly lowered by 10°C?
• The solubility of #KNO_3# is 155 g per 100 g of water at 75° Cand 38.0 g at 25°C. What mass (in grams) of #KNO_3# will crystallize out of solution if exactly 100.0 g of its saturated solution at 75° C is cooled to 25°C?
• A student determines that 8.2 milligrams of oxygen is dissolved in a 1000 gram sample of water at 15°C and 1.0 atmosphere. In terms of saturation, what type of solution is this sample?
• Water can hold 36 grams (g) of salt in every 100 milliliters (mL). The ocean contains 3.6 g of salt in every 100 mL. As a solution, is seawater resaturated, saturated, or unsaturated?
• Question #796e9
• How do we do we demonstrate a #"saturated solution"#?
• What is the total mass of #KNO_3# that must be dissolved in 50 grams of #H_2O# at 60°C to make a saturated solution?
• How many total moles of #KNO_3# must be dissolved in water to make 1.5 liters of a 2.0 M solution?
• What is the mass of #NH_4Cl# that must dissolve in 200 grams of water at 50°C to make a saturated solution?
• A saturated solution of potassium chloride at #60# #""^@C#, is cooled to #20# #""^@C#. What happens, and how do we describe the solutions?
• In 100 g of water at 0°C, table sugar has a solubility of 180 g. What will happen if you add 100 g of table sugar to 50 g of water at 0°C?
• How does a saturated solution relate to a supersaturated solution?
• A solution contains 35 grams of #KNO_3# dissolved in 100 grams of water at 40°C. How much more #KNO_3# would have to be added to make it a saturated solution?
• Question #7ba31
• How is an #"unsaturated solution"# defined?
• Question #4a5bb
• What causes a saturated solution to form?
• When and how does a solution become #"supersaturated"#?
• Question #d9627
• Will a solution made by adding 9,0 g #NH_4Cl# to 20 g of #H_2O# be saturated or unsaturated at 50 degrees C?
• How do I know whether a solution of potassium nitrate in water is saturated?
• How is a saturated solution of sodium nitrate prepared?
• What is the maximum amount of #"KCl"# that can dissolve in 300 g of water at 20°C?
• Question #824b6
• Question #b551e
• What is meant by the term saturated?
• How could you tell that a solution was reaching its saturation point?
• What would happen if more solute is added to a solution after the saturation point reached?
• A solution is made by dissolving 55 g of #KNO_3#, in 100 g of water at 60 degrees C. Is this solution saturated, unsaturated, or supersaturated?
• Question #4b253
• What volume of a 0.855 M KOH solution is required to make a 3.55 L solution at a pH of 12.4?
• If #541*g# of calcium is reacted with water to give a #1*L# volume of solution, what is #[Ca^(2+)]#?
• What is a solution that contains more solute than it would normally hold at that temperature said to be?
• If 55 grams of #KCl# are dissolved in 100 grams of water at 80°C is the solution saturated unsaturated, or supersaturated?
• What happens when a supersaturated solution of Borax cools?
• What is the process in which hydrogen is introduced to vegetable oils to make them saturated known as?
• A solution contains 14 g of KCI in 100. g of water at 40°C. What is the minimum amount of KCI that must be added to make this a saturated solution?
• How would you classify the following compounds as saturated, unsaturated, or substituted hydrocarbons: hexane (#C_6H_14#), isopropyl alcohol (#C_3H_7OH#), 2-chlorobutane (#C_4H_9Cl#), pentene (#C_5H_10#), and butyric acid (#C_3H_7COOH#)?
• How can you determine if the solutions made in a lab were saturated?
• What is the tempeature to which air must be cooled at a constant pressure to become saturated?
• Question #76da3
• What occurs in a saturated solution, when the solvent evaporates? Does it remain saturated?
• Vegetable oil is saturated or unsaturated?
• Question #3c69b
• When does the air become saturated?
• Are "unsaturated", "saturated" and "supersaturated" examples of variable composition?
• A seed crystal was placed in a super-saturated solution. When crystals of solute formed, the resulting process was exothermic (felt warm). Why?
• What is the difference between precipitation and crystallization?
• How can a saturated feature can become supersaturated?
• What is a good analogy for a saturated solution?
• After a solution undergoes crystallization, is the remaining solution saturated, or unsaturated?
• What is the ratio of actual water vapor the air to the amount of water vapor needed to reach saturation content?
• A mass of 80 g of #KNO_3# is dissolved in 100 g of water at 50°C. The solution is heated to 70°C. How many more grams of potassium nitrate must be added to make the solution saturated?
• A solution of potassium chlorate, #KCIO_3#, has 20 grams of the salt dissolved in 100 grams of water at 70 C. Approximately how many more grams of the salt can be added to the solution before reaching the saturation point?
• What is the solubility of #"barium sulfate"# in a #250*mL# volume of #0.01*mol*L^-1# #"sulfuric acid"#?
• What is an unsaturated hydrocarbon with a triple bond and two carbons?
• In unsaturated fats, what is missing in the fatty acid chain?
• Question #fe5b8
• In a saturated hydrocarbon, what are all the bonds?
• Question #055ce
• Question #18716
• What is the difference between an unsaturated solution and a saturated solution?
• What is the general formula of an unsaturated hydrocarbon?
• A student prepares four aqueous solutions in 100 g of #H_2O# at 20 °C: 120 g of #KI#, 25 g of #KCI#, 88 g of #NaNO_3#, and 5 g of #KCIO_3#. Which solution is saturated?
• Question #91637
• Question #d6ffb
• How is a saturated solution in water prepared from a given solute?
• I have a question ... in my method of measurements of Moisture in Cosmetics by the distillation technique, it is recommended to use Saturated toluene (saturated with water). Can you inform me how to prepare this saturated solution of toluene and water?
• Why are saturated fats generally found a in a semi-solid state and unsaturated fats found as oils?
• Fat triglyceride molecules have more hydrogen on their fatty acids and are usually solid at room temperature. Which type of fatty acid (saturated or unsaturated) is more common in fat triglycerides?