+CHEM--關於osmosis同chemical equation

Royal

1) 擺一個載滿20%sucrose solution既dialysis tubing落distilled water度，
　佢地會做osmosis，咁呢個osmosis直至幾時先停止呢?
　會唔會係兩個既water potential都一樣(sucrose solution同distilled water)...但照計都冇乜可能架
　我本書(二手書)就畫左係會o係hydrostatic pressure = water gradient force果時停...都唔知乜o黎..
　之前睇左d網頁就話係water potential = solute potential + pressure potential...更加唔知乜o黎...
　我想問如果CE叫我解釋osmosis幾時停止既話，我應該點答？

2) chem有redox reaction, precipitate reaction....仲有好多
　KI + Ag2SO4 既話...
    應該係2KI(aq) + Ag2SO4(aq) --> K2SO4(aq) +2AgI(s)
　定係half-eqt: 2I- --> I2+2e- (x1)
　　　               Ag+ +e- --> Ag (x2)
            ionic eqt: 2I-(aq) + 2Ag+(aq) --> I2(aq) + 2Ag(s)
            full eqt: 2KI(aq) + Ag2SO4(aq) --> I2(aq) + 2Ag(s) + K2SO4(aq)
　點解好似兩個都得既？？-3-

如果大家覺得我問d問題好愚蠢既話，請多多包涵，因為我真係咁蠢-3-

fish

原帖由 Royal 於 29/9/2007 01:43 PM 發表

1. When water potential between the two liquid are equal, there will be no net movement of water(solvent) molecules. Osmosis stops.
hydrostatic force是force of water acting on a surface吧.....

2. Temp. deleted

[ 本帖最後由 fish 於 29/9/2007 02:59 PM 編輯 ]

Royal

原帖由 fish 於 29/9/2007 02:28 PM 發表


1. When water potential between the two liquid are equal, there will be no net movement of water(solvent) molecules. Osmosis stops.
hydrostatic force是force of water acting on a surface吧.....

...

ECS裡面, Ag+ o係I-既左下面...同埋d人又話ECS唔可信-3-
咁我其實應該點分幾時ppt reaction, 幾時redox??

thx~

fish

原帖由 Royal 於 29/9/2007 03:01 PM 發表

ECS裡面, Ag+ o係I-既左下面...同埋d人又話ECS唔可信-3-
咁我其實應該點分幾時ppt reaction, 幾時redox??

thx~

就是剛剛記起 Ag在I下面才delete的.....
ECS不能盡信.....因為還有其他factor可以affect if the reaction will occur

剛看回了書書....原來我沒錯-w-
是PPT reaction為major reaction
因為後者是較慢,所以以ppt rxn為主要rxn

[ 本帖最後由 fish 於 29/9/2007 03:22 PM 編輯 ]

STEVE

原帖由 fish 於 29/9/2007 03:12 PM 發表


就是剛剛記起 Ag在I下面才delete的.....
ECS不能盡信.....因為還有其他factor可以affect if the reaction will occur

剛看回了書書....原來我沒錯-w-
是PPT reaction為major reaction
因為後者是較慢,所以 ...

好像AgI只要用陽光一照就會打回Ag+I2?

elven2001

原帖由 STEVE 於 29/9/2007 06:00 PM 發表

好像AgI只要用陽光一照就會打回Ag+I2?

補充:以Ag2O作為正常觀察

[ 本帖最後由 elven2001 於 29/9/2007 06:49 PM 編輯 ]

fish

原帖由 STEVE 於 29/9/2007 06:00 PM 發表

好像AgI只要用陽光一照就會打回Ag+I2?

是的,但CE 數年前delete了此類的photochem.我就懶打了-v-