Which one of the following is a redox reaction? . 2 na(g) + cl2(g) 2 nacl(s) a. k2cr2o7(aq) + 2 koh(aq) 2 k2cro4(aq) + h2o(l) b. h2o(l) h+(aq) + oh -(aq) c. na2co3(s) + 2 hcl(aq) 2 nacl(aq) + co2(g) + h2o(l) d. ba2+(aq) + so42-(aq) baso4(s)

Electron equations of the given changes are as follow,a)                              cu      →      cu⁺²  + 2e⁻b)                              mg⁺²  +  2 e⁻      →      mgc)                              cl⁻    →      cl  +  1e⁻d)                              s  +  2 e⁻    →      s²⁻e)                                o²⁻      →      o  +  2 e⁻f)                              p  +  3 e⁻    →      p³⁻g)                              fe²⁺    →      fe³⁺  + 1 e⁻h)                              s²⁻    →      s⁴⁺  +  6 e⁻

For lesson: cameras, plant presses, newspaper, paper towels, clip boards, pencils, calculators, field guides, metric measuring tapes, paper, transect squares, colored pencils, ph meters, light meters, computers, etc.for extension: baggies for soil samples collecting, distilled water, hand shovels, beakers, boiled rice, microscopes, well microscope slides or regular microscope slides with cover slips