Give two examples of reversible processes and two examples of irreversible processes in purely mechanical systems, such as blocks sliding on planes, springs, pulleys, and strings. Explain what makes each process reversible or irreversible.
Chapter 9: November 5, 2015 Aqueous Reactions 1. Some ionic compounds and molecular acids dissociate and ionize respectively in H2 to form ions a. ionic compounds: solubility rules (see slide 9 from presentation) b. molecular acids: acid strength → strong acids 2. Precipitation Reactions: occurs when you take two solutions, mix them, and a solid is created; this solid is known as tprecipitate a. this solid must be insoluble in2 i. to determine this, go back to the solubility rules! 3. Ex: KI (aq) + Pb(NO32 ) To see if this reaction is possible and determine products: a. Are the reactants soluble in 2 Check the solubility rules, KIyes, lead nitrateyes b. If yes, dissociate them into ions. i. make sure to check the charges! K+ + Pb+ NO 1 3 c. Determine the possible products by combining the cation from one reactant and the anion from the other reactantNO + PbI 3 2 i. Make sure that this is reduced to the lowest whole number d. Ask yourself, is the product soluble or insoluble in water i. If soluble, it is aqueous and they are ions in the soluNO.3q) ii. If insoluble, they will be solids and they will crash out of the solution (precipitate!)PbI2
