chem 06 mc Q33,40

Q.33
類似sacrificial metal
when zine loses electrons, the electrons go to the copper metal
because, the electrons through from
higher reactive metal to less reactive metal.
H+ ions gain electrons
2H+ + 2e- ----〉 H2
so the gas(H2) from on the surface of the copper plate

Q.40
個Cu2+ 的濃度要兩邊一樣,
換言之,左手邊的Cu要變Cu2+(lose electrons)去增加Cu2+的濃度
Cu ---〉Cu2+ + 2e-
右邊的Cu2+要變Cu(gain electrons) 去減少Cu2+的濃度
Cu2+ +2e- ---〉Cu
所以electrons由electrodeX to electrode Y(個圖錯的)

同以上所講一樣,左手邊的Cu要變Cu2+ (mass decrease)
右邊的Cu2+要變Cu(mass increase)