CHEM 210 Quiz 1 with 100% correct answers

What are the Bronsted-Lowry definitions of acid and base? Acids donate H+ and Bases accept H+ (BAAD) What is the difference between a strong acid and a weak acid? Give examples of each. Strong acids completely dissociate into anion and H+. Weak acids do not dissociate completely into anion and H+, they form an equilibrium system and reform acid and anion and H+ continuously. Strong acid ex. HCl and H2SO4 Weak acid ex. H3PO4 and HC2H3O2 What is the difference between a strong base and a weak base? Give two examples of each. Strong bases completely dissociate into the cation and OH-. Weak bases do not completely dissociate into cation and OH-, they form an equilibrium system and reform base and cation and OH- continuously. Strong base ex. NaOH, KOH Weak base ex. NH3, NH4OH What is a polyprotic acid? Give a specific example. Polyprotic acids can lose many H+'s per molecule, also can write many reactions as a result of losing the multiple H+. Specific example: H3PO4 Write the three balanced chemical reactions between H3PO4 and NaOH. H3PO4+NaOH--->NaH2PO4+H2O H3PO4+2NaOH--->Na2HPO4+2H2O H3PO4+3NaOH--->Na3PO4+3H2O Write the three Ka expressions for H3PO4 and list the numerical values of each. H3PO4+H2O-->/<--H2PO4^- + H3O^+ H2PO4^- + H2O-->/<--HPO4^2- + H3O^+ HPO4^2- + H2O-->/<--PO4^3- + H3O^+ ACTUAL Ka expressions: [H2PO4^-] [H3O^+]/[H3PO4] Ka: 5.9x10^-3 [HPO4^2-] [H3O^+]/[H2PO4^-] Ka: 6.2x10^-8 [PO4^3-] [H3O^+]/[HPO4^2-] Ka: 4.8x10^-13 What is a conjugate acid and conjugate base? What is the acid-conjugate base pair in the Ka,1 expression for H3PO4? Conjugate acid is a compound formed when the base accepts H+ from the acid. Conjugate base is a compound formed when the acid loses H+. H3PO4 (acid) and H2PO4^- (conjugate base) What is the mathematical relationship between Ka, Kb, and Kw for an acid-conjugate base or base-conjugate acid pair? KaxKb=Kw Sketch the titration plot that you would expect to obtain for complete titration of 25 mL of 0.10 M H3PO4 with 0.20 M NaOH, indicating clearly the number of equivalence points and their volumes. number of eq points-3 Volumes of points: 12.5, 25, and 37.5 mL Calculate the equivalence point volumes for a titration of 25 mL of 0.060 M HCl and 0.10 M H3PO4 with 0.075 M NaOH. There will be 2 of them. 53.33 and 86.67 mL? idk