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單項(xiàng)選擇題

已知反應(yīng)6Fe2++Cr2O72-+ 14H+= 6Fe3++ 2Cr3++ 7H2O在常溫下可自發(fā)進(jìn)行,則該反應(yīng)組成的原電池的符號(hào)為()

A.(?)Fe(s)│Fe2+(c1), Fe3+(c2)║Cr2O72-(c3), Cr3+(c4), H+(c5)│Pt(s)(+)
B.(?)Fe2+(c1), Fe3+(c2)║Cr2O72-(c3), Cr3+(c4), H+(c5)│Pt(s)(+)
C.(?)Pt(s)│Cr2O72-(c3), Cr3+(c4),H+(c5)║Fe3+(c2),Fe2+(c1)│Pt(s)(+)
D.(?)Pt(s)│Fe2+(c1), Fe3+(c2)║Cr2O72-(c3), Cr3+(c4),H+(c5)│Pt(s)(+)

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