Write the symbolic notation of an isotope of an element having 8 protons, 8 electrons, and 11 neutrons.

Which one of the following is an oxidation-reduction reaction? naoh + hno3 --> h2o + kno3 naoh + hno3 --> h2o + kno3 so3 + h2o --> h2so4 cacl2 + na2co3 --> caco3 + 2 nacl ch4 + 2 o2 --> co2 + 2 h2o al2(so4)3 + 6 koh --> 2 al(oh)3 + 3 k2so4

Pl what kind of reaction is this? nahco3 + h2o → co2 + naoh + h2o -composition -decomposition -single replacement -double replacement im leaning more toward single replacement. if im wrong can you explain whyy?

Which of the following reactions represents an exothermic reaction? nh3(g) + 12.0 kcal ½n2(g) + 3/2 h2(g) ch4 + 2o2 co2 + 2h2o + 212,800 cal c + 2s cs2, h = 27,550 cal c(graphite) c(diamond), h = 0.45 kcal 2h2o 2h2 + o2, h = +58 kcal