Presentation on theme: "Saturated A saturated solution is one that has dissolved in it all the solute that it can normally hold at that temperature If it has less than the max."— Presentation transcript:
Saturated A saturated solution is one that has dissolved in it all the solute that it can normally hold at that temperature If it has less than the max amount of solute possible, it is unsaturated
Supersaturated Solution hold more solute than is present in their saturated solutions Produced by creating saturated solution at high temp and allowing it to gradually cool
Electrolyte Solutes in aqueous solutions as ions Strong Electrolyte – solute ionized completely (highly soluble salts or very polar covalent compounds) NaCl → Na + + Cl - Weak Electrolyte – incomplete ionization occurs (poorly soluble salts or weekly polar) HgCl 2 ↔ HgCl + + Cl - only a small part of the HgCl 2 that is dissolved is present as ions
Non-electrolyte – no ionization occurs (non-polar covalent subtances) Ionic solutes and some very highly polar molecular solutes are electrolytes
Acids and Bases They are electrolyte solutions Strong Acid or Base is completely ionized Weak Acids or Bases are not ionized completely
Concentration of Electrolytes If each compound below is a strong electrolyte, what is the total concentration of solute particles for each 1) 1.5 M NaCl 2) 0.50 M MgCl 2 3) 0.25 M Ca(NO 3 ) 2 4) 2.5 M K 2 S 5) A mixture of 10 ml of 0.20 M NaCl and 20 ml of 0.40 M Ca(NO 3 ) 2
Vapor Pressure When solutes are added to a solvent, the solvent molecules no longer evaporate at the same rate but they still condense at the same rate Solution end up with lower vapor pressures than pure solvent
What Is Happening?
Raoult’s Law Vapor pressure of a solution lowers at an extent proportional to the concentration P A = X A P A ° P A – vapor pressure of solution X A – mole fraction of the solvent P A ° - vapor pressure of pure solvent
Example Calculate the new vapor pressure of a solution formed by the addition of 100g of sucrose, C 12 H 22 O 11, to 1000 g of water, if the vapor pressure of the pure water is 23.8mmHg.
Ideal Solutions Solvent and solute are alike in size, strength, and type of interactions When solution isn’t ideal Raoult’s Law is off If interactions between the solute and solvent molecules is weaker than ideal, the vapor pressure difference will be less than predicted by Raoult’s Law