solutions

solutions

1. definition: homogeneous mixture of variable composition in a single phase.

2. Solvent: the most abundant substance in a solution.

3. solutes: the dissolved substances

4. Solutes dissolved in a solvent make a SOLUTION!

   • Three types of solutions: solid, liquid, gaseous
     • Example of liquid solution: rubbing alchohol
     • Example of solid solution: metal alloys

5. miscible: describes when two liquids mix to form a homogeneous mixture. (liquid-liquid solution)

6. liquid solution is formed when the solvent is a liquid

7. immiscible: described when liquids separate after mixing (example: oil and vinegar)

8. bonus

   • amalgam: a solution containing mercury
     • volumetric flasks: special pieces of glassware that carefully calibrate to yield exact amounts of solutions.
       • colloids: particles that are visible and suspended

9. Gaseous solutions can only dissolve other gasses NOT LIQUID OR SOLID

   • the solute and solvent mix by diffusion

10. solvation: dissolving process in solid-in-liquid solutions

    • explained: the molecules of the solvent surround and separate the ions or molecules of the solute.
    • hydration: solvation in water
    • dissociation: if the solute is an ionic compound, the solvent molecules break up the crystal into ions
    • ionization: process in which covalent compounds form ions when they dissolve in a solution
    • Steps in solvation
      • 1. heat is absorbed from surroundings (endothermic); causes a separation
        • 2. solute and solvent particles mix and begin to attract each other; energy is released and a stable arrangement of particles is formed
          • enthalpy (heat) of solution: the net energy change during dissolving process
            • expressed as kj/mol

11. Thermal energy is required to overcome the intermolecular forces between the solvent and solute

12. like solvents dissolve like solutes

13. soluble: when a solute is able to desolve in a solvent

14. solubility: the maximum amount of a solute that can dissolve in a specific solvent (under specific conditions such as temp and pressure.

15. insoluble: when a solute's ions are so tightly bound, the solvent is unable to break it apart.

16. unsaturated: when a solute has not yet reached it's maximum solubility, the solution is..

    • effervescence: the escape of a gas from a liquid-gas solution
      • concentration: the number of solute particles in a certain volume or mass of the solvent
        • concentration = amount of solute/ amount of solution
        • percent by mass: ratio that compares mass of the solute to the mass of the solution (concentration ; multiply by 100%)
          • percent by volume: ratio that compares the volume of the solute to the volume of the solution (concentration ; multiply by 100%)

17. saturated: when a solution contains the maximum amount of solute at a given temp

18. dynamic equilibrium: the rate of the forward reaction equals the rate of the reverse reaction.

19. supersaturation: occurs when a solution contains more dissolved solute than it does at equilibrium.

20. the rate that a solute dessolves depends upon it's solubility and the frequency of collisions with the solvent particles. (temp, stirring, surface area of solvent)

21. higher temp increases solubility and increases collisions

22. when gases dissolve, HEAT is RELEASED

23. Henry's Law: "the solubility of gases is directly proportional to the partial pressures of the gases above the solutions."

    • S1/P1 = S2/P2
      • S = solubility of two different gases
        • P = partial pressures above the gas-liquid solution

24. molarity(M): the number of mols of solute per liter of solution.

    • Chapter 12 section B
    • molalty (m): the number of moles of solute per kilogram of solvent.
      • mol of solute/ Kg (mass) solvent
      • osmosis: the process in which a solvent moves across a semi-permeable membrane.
        • osmotic pressure: the amount of pressure required to prevent osmosis from occuring.
          • colligative property
          • isotonic: when concentrations on both sides of the membrane are equal
            • hypertonic: the solution on the outside of the cell is MORE concentrated then the inside of the cell.
              • results: water flows out of the cell, the cell shrivels
              • hypotonic: the solutoin on the outside of the cell is LESS concentrated than the inside of the cell.
                • results: water flows into the call, the cell burst
    • mol of solute/ L solution