Chemistry 化學問題

Air唔係compound係mixture coz只要將d liquefied air擺係個fractional tower度加熱就可以分返出carbon dioxide, oxygen, nitrogen等等ge gas出黎, 係physical ge break down唔需要chemical ge break down. air唔係molecule, 佢裡面ge carbon dioxide係molecule, oxygen係molecule, vapour係molecule, nitrogen係molecule.不過佢地加埋就唔係moleule係particle.
Ethanol係compound, 屬於covalent compound, 佢唔可以用pysical ge method去break down開做返其他更細ge molecule. 要將佢break down有好多種方法, 視乎你想將佢點拆.係molecule.
Sucrose同ethanol ge情況一樣, 係compound同埋molecule.


***一樣野係compound ge話就唔係mixture,但係mixture裡面就可以有compound ge molecule係度,eg1.一隻杯有紅豆加綠豆(當紅豆同綠豆係element),個杯野係mixture, 兩種豆個性質(nature)都無變到, 一樣可以見到紅豆係紅色, 綠豆係綠色, 兩種野無combine埋一齊, 係一杯得element ge compound, 而當中每一粒豆都係一粒molecule...eg2.將一舊紅色ge泥膠同一舊藍色ge泥膠搓埋一齊, 出左黎紫色ge泥膠係一舊compound, 兩舊泥膠ge性質都唔同左, 紅色ge泥膠無左紅色, 藍色泥膠無左藍色, 成舊野多左個nature, 叫做紫色, 兩種唔同ge molecule combine埋一齊, 又唔可以用physical ge方法將佢地分開所以係compound. 而一粒紅色ge molecule combine with一粒藍色ge molecule出左黎個粒紫色都係一粒molecule...eg3將舊紫色泥膠揉成一粒粒好似豆咁大粒, 倒埋入頭先杯紅豆加綠豆度, 依加隻杯裡面ge粒粒都無combine係一齊, 依然見到紫色ge泥膠, 紅色ge紅豆, 綠色ge綠豆, 仲聞得返紫色泥膠d臭膠味, 三種野都無改變自己ge性質, 而又無新有一種性質出黎, 所以杯野依然係一杯mixture, 不過今次杯野裡面係有包含住compound(紫色泥膠)同埋element(紅豆同綠豆) ge mixture.


希望我d example可以幫到你理解點分compound同mixture啦, coz compound and mixture係一個好basic而係chem裡面又好重要ge concept黎架~

2007-02-05 09:06:12 補充：
sorry之前打錯少少野eg1.一隻杯有紅豆加綠豆(當紅豆同綠豆係element),個杯野係mixture, 兩種豆個性質(nature)都無變到, 一樣可以見到紅豆係紅色, 綠豆係綠色, 兩種野無combine埋一齊, 係一杯得element ge MIXTURE, 而當中每一粒豆都係一粒molecule...

Air is mixture,it is made up by many kinds of gases.
Ethanol is compound and molecule ,not mixture.
Sucrose is compound and molecule ,not mixture.