A solution contains both iron(II) and iron(III) ions. A 50.00 mL sample of the solution is titrated with 34.80 mL of 0.02800 M KMnO4, which oxidizes all the Fe2+ to Fe3+. The permanganate ion is reduced to manganese(II) ion. Another 50.00 mL sample of the solution is treated with zinc, which reduces all the Fe3+ to Fe2+. The resulting solution is again titrated with 0.02800 M KMnO4; this time 47.80 mL is required. What are the concentrations of Fe2+ and Fe3+ in the (original) solution?

Which traits do human embryos have that link them to a common ancestor with fish and reptiles? a. scales and tail b. gill slits and scales c. tail and gill slits d. hair and tail

16. why must the number of electrons lost equal the number of electrons gained in every redox reaction? use 3 – 4 sentences in your own words to address this question. 18. what type of radiation is emitted when chromium-51 decays into manganese-51? show the nuclear equation that leads you to this answer. 19. a radioactive nucleus alpha decays to yield a sodium-24 nucleus in 14.8 hours. what was the identity of the original nucleus? show the nuclear equation that leads you to this answer.

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory