13-20. A 4.912-g sample of a petroleum product was burned in a tube furnace, and the SO2 produced was col- lected in 3% H,O,. Reaction: SO- + H,O, → H;SO, A 25.00-mL portion of 0.00873 M NAOH was intro- duced into the solution of H,S04, following which the excess base was back-titrated with 15.17 mL of 0.01102 M HCI. Calculate the sulfur concentration in the sample in parts per million. *13 31

STARTING AMOUNT esc C X C 2 F2 W # 3 1000 F3 ADD FACTOR x( ) $ 4 1 97.9 FS de in % 5 2 Convert 23.4 kJ to calories 2.34 x 104 t 4184 kcal 6 P 0.001 J 4.184 COMEC DOLL ANSWER & 7 9.79 × 104 cal 00 8 RESET FO 2 23.4 ( 5590 A FIT 120 Jan 21 del +

f) 0 Baz OEt ? OEt

Cl₂(g) + 2e Cr₂0 (aq) + 14 H(aq) + 6e¯ 02(g) +4H(aq) + 4e¯ MnO2(s) + 4H(aq) + 2e 103 (aq) +6H(aq) + 5e¯ VO₂ (aq) + 2H(aq) + e¯ Br₂() + 2e NO, (aq) + 4H(aq) + 3e¯ ClO2(g) + e Ag+(aq) + e 2 CT (aq) 1.36 2 Cr3+(aq) + 7 H₂O(1) 1.33 2 H₂O(1) 1.23 Mn2+(aq) + 2 H2O() 1.21 12(aq) + 3H2O(l) VO2+(aq) + H2O(l) 1.20 1.00 2 Br (aq) 1.09 NO(s) + 2 H2O(l) CIO₂(aq) 0.96 0.95 Ag(s) 0.80 0.77 Fe3+(aq) + e Fe2+(aq) A mixture of Fe3+, CIO₂, and Cr₂O,² was made, what reaction would be predicted, if any? a. Fe3+ + Cr2O7²- b. Cr2O + Clo²- c. Fe3+ Clo²- d. No reaction. -> -> Fe²+ + Cr³+. - Cr3+ + ClO2. Fe²+ + ClO2.