CHM 2045C                                                               Name:___Answers

Module 8 Sample Pretest


Module 8: Solutions Chapter 5

Part B: Factors Affecting Rate of Dissolving    5 points


State two factors greatly affecting the solubility of a gas in a liquid:


(1) Temperature (increased temperature of a solvent also generally increases the kinetic energy of the solute  and the gas solute acquire more of a tendency to escape from the solvent. Therefore, Cooling the solvent increased the solubility of a gas in a liquid solvent.)



(2) Pressure (increasing the pressure (partial pressure) of a gas solute increases the solubility proportionally of that solute in the liquid (Henry’s Law)



What is the main factor affecting the solubility of a liquid in a liquid:



(3) Nature of the solute and solvent: the like dissolves like rule. The general principle that solubility is greatest when the polarity of the solute is similar to that of the solvent



State four factors which governs the rate of dissolving a solid in a liquid:


1.  Particle Size (increased surface area increases rate of solution)



2. Temperature (increased temperature of solvent generally increases rate of solution,

     except gases in liquids is opposite)



3. Concentration of Solution- when the solute and solvent are first mixed the rate of dissolving is at a maximum, as saturation approaches the rate of dissolving slows



4. Agitation or stirring-the effect of agitation is kinetic which incresesthe rate of solution .