L1 - Solutions - PP Flashcards
The solute
Is the substance which is dissolved
The solvent
Is the substance in which the solute is dissolved
Dilute solutions
Amount of solute is small compared to solvent
Concentrated solutions:
Amount of solute is larhe compared to solvent
Saturated solutions:
No more solute can be dissolved by the solvent in the presence of excess solute
Density:
Mass (m) per unit volume (V). Symbole of density is “p”
Isotonic solution;
A solution with the same osmotic pressure as blood, such as 0,9 percent NaCl, is an isotonic solution.
Hypotonic solution
In a hypotonic solution, lower solute concentration than blood., water flows into the red blood cells which eventually burst (hemolysis)
Hypertonic solution
In a hypertonic solution, higher solute concentration than blood, water flows from the red cell which shrinks (crenation).
Crystalloids
Crystalloids are solid solutes which form true solutions, can pass through filters and animal membranes, can be crystallized from solutions.
Suspensions
Suspensions are solid solutes which do not dissolve and are so heavy that they settle out.
Colloids
Colloids are solid solutes, of a size in between crystalloids and suspension, which do not dissolve as crystalloids, but which are light enough so that they don’t settle down. May pass through filters but not animal membranes. Cannot be crystallized from solution.
Sol
Sol is a liquid colloidal solution; gel is a solid colloidal solution.
Colloid osmotic pressure;
Colloid osmotic pressure is the osmotic pressure which occurs as the result of the presence of a colloidal (impermeable) on one side of two compartment system separated by a semipermeable membrane, such as in the blood capillaries.
True solutions:
Is a homogenous mixture of two or more substances at the molceular level. The components of a solution are known as the solute and the solvent.
Arrhenius theory:
Arrhenius theory: An acid produces H+ in water solution;
A base produces OH- in water solution.
Bronsted-Lowery theory:
The Bronsted-Lowery theory is the most prevalent of the 3 theories in organic chemistry.
- An acid is a proton donor.
- A base is a proton acceptor.
- Bases have conjugate acids.
- Acids have conjugate bases.
- The conjugate base is the remaining particle of the acid after a proton is released.
Lewis theory:
Lewis theory: An acid is an electron pair acceptor; a base is an electron pair donor.
Kw:
Kw – Ionic product for water.
Kw = [H+] [OHˉ] = 1∙10^-14
Litmus color change:
Litmus changes color from red to blue as the pH of a solution increases from pH 6 to pH 8.
Phenolphthalein color change:
Phenolphthalein goes from a colorless form to red as the pH of solution increases from pH 8 to pH 10.
When are strong acids and bases are completely ionized?
Strong acids and bases are completely ionized in dilute aqueous solutions. Other acids and bases, because they ionize incompletely in water (often to the extent of only a few percent), are called weak acids and bases.
Equivalence point of a titration:
Equivalence point of a titration is where the two substances were mixed in exactly equation proportions. Obviously there is need to choose an indicator which changes.
The end point:
The end point is the point at which the titration is stopped.
When will you not use an indicator?
One would never titrate a weak acid and a weak base in the presence of an indicator.
