chem redox 問題

timmy3221

請問點為知有redox reaction..
點分 O.A 同埋 R.A
同埋ionic half eq. 同 overall eq. 點寫

希望各位chem高手幫幫小弟!!
我睇左好耐都唔明-3-
我聽日ch. test,,唔想0分咁樣衰-_____-

-終場ソ使者-

Lose of e^- is oxidation,
gain of e^- is reduction.
Redox reaction:both red. and ox. occur-.-
half equation:
Mg->Mg²⁺+2e^-
is one kind of oxidation(O.N. increases)
Cu²⁺+2e^-->Cu
is reduction(O.N. decreases)
overall equation:
Mg+Cu²⁺->Mg²⁺+Cu

timmy3221

thanks ;-)
咁有條eq要加H+//e-同埋H2O係咩黎嫁?

[S]Mangoray

MnO4- + 8H+ + 5e- ---> 4H20 + Mn2+
half equation代表要在H+(aq)情況下先做倒反應

-終場ソ使者-

佢地之所以有H⁺同H₂O
係因為MnO₄^-->Mn²⁺(以樓上既為例)既LHS有O,RHS冇
咁d O點黎?就係係H₂O到(因為H₂O係存在係MnO₄^- solution到)
RHS多左D H,LHS就要補番H⁺
(balance個陣要+H₂O先,之後+H⁺,之後+e^-,以呢個次序balance係最好)

timmy3221

ic..
thx..
雖然係quiz仔,,
但係我好似都錯哂-____-
唉`chem真係好難-v-

[S]Mangoray

讀下讀下你就會發覺好易,,,黎黎去去都係咁
概念鞏固既話,基本上計數果part拎硬90%分

-終場ソ使者-

萬變不離其中@@