QUESTÃO 1 - A equação que representa corretamente a combustão total do eteno, C2H4, é * A) C2H4 + O2 = 2 CO2 + 2 H2O B) C2H4 = 2 CO2 + 2 H2O C) C2H4 + 2 O2 = 2 CO2 + 2 H2O D) C2H4 + 3 O2 = 2 CO2 + 2 H2O E) C2H4 + 4 O2 = 2 CO2 + 4 H2O

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.