Предмет: Химия, автор: НикаЛика120

Составьте Уравнения окислительно - восстановительных реакции:
А) Са + О2 ->
Б) Zn + O2 ->
В) Сu + O2 ->
Г) Са + Н2О ->

Ответы

Автор ответа: anassstass
4
а) Ca (0) + O2 (0) — Ca (+2) O (-2)
Ca (0) - 2ē — Ca (+2) восстановитель
O2 (0) + 4ē — 2O (-2) окислитель
2Ca + O2 — 2CaO

б) Zn (0) + O2 (0) — Zn (+2) O (-2)
Zn (0) - 2ē — Zn (+2) восстановитель
O2 (0) + 4ē — 2O (-2) окислитель
2Zn + O2 — 2ZnO

в) Cu (0) + O2 (0) — Cu (+2) O (-2)
Cu (0) - 2ē — Cu (+2) восстановитель
O2 (0) + 4ē — 2O (-2) окислитель
2Cu + O2 — 2CuO

г) Ca (0) + H2 (+) O (-2) — Ca (+2) (OH)2 (-) + H2 (0)
Ca (0) - 2ē — Ca (+2) восстановитель
2H (+) + 2ē — H2 (0) окислитель
Ca + 2H2O — Ca(OH)2 + H2
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