Question

Topie 1 Review question an concentrations of salutions (preparation, dilution, and se of the solution). For exam ple What is the molar concentration of calcium hydroxide in a salution prepared by dissalving 0.2478 grams of calcium hydroxide in cnongh water to make 40.00 mL of salution? -If the solution above is diluted to 100.00 mL, what is the molarity of calcinm hydroxide in the new salution? -Eanus: what is the pH of the oniginal solution and the diluted solution? Note: the questions above are meant to be a representative example of the class of concentration type que stions. Fou should be able to sohve ary similar question-7ot only the ezample given above. Topie 2: Review question on interm alecular forces and solubility. Here is an exam ple Will the compound phospborus trichlonide dissolve in water or noc? Provide a complete justification for your answer. Note: the question above is meant to bea representative example of the class of questions covering intermoleciular forces and solubility. You sho uld be able to answer any similar type of question-rot only the example given above. As we discussed in lecture during the demo, here are poirts that should be covered to justify your answer: First, have the correct chemical formula from the textual name of the compound Write the best Lewis structure for the compound Explain how you use the Lewis structure and the VSEPR theory to find the shape. Why is knowing the shape importart? Evaluate each bo nd arownd the certral atom for ary dipole momeras and explain the evahuation Using shape AND dipole momerts (or the lack thereof) explain how to arrive at the overall polarity of the mo lecule From the overall po larity of the mo lecule, explain how to determaine the primary intermolecular force for the compo ond Finally, explain how the types of intermolecular forces relate to the decision on so hubility. All of these items are needed to have a complete justification. Topic 3: Be able to apply the equilibrium constant expression for the dissociation of water (K) in order to find the hydronium ion concentration when given the hydroxide ion concentration-or-find the hydroxide ion Concentration when given the hydromium ion concentration Also be able to calculate the pH of the salution (with the corect num ber of significant figures). Topie 4 When given the pH of a solution, be able to calculate both the hydronium and hydroxide ion concentrations in the solution.

Answer 1

Caloto mass = 0.24 78 9 molas nous = 74 g/mol Volume = Home = 40 x16 3L Molonity - mass = 0.2478 g I molo mass xvolcune (2) 74&molt x yoxlo34 M = 0.08371 mall 1 ) Using Molarity equation My = Mrr stock diluted solecion 0.08371 M X you = MX looml Molit = 0.0335m ! iluted Selate Calotily Calt & 2014- [calon ] = [ (92+ ] = [on] [an] = 2x0.0335 0.06697 M pol= -log Ton] → pOH = 1194 pH = 14 poll a pH = 12:3267 1 Diluted Stock solution [ost] = b 2.0.08371 M = 0.16942M pot= -log [or) POH = 0.796 [PH = 13.22k- original in