CHEM高手入,有問題!!!

＊ＥｒＩｃ＊

我想問點知2種既ionic compound既aq state,即係solution,溝埋有冇反應?=v=.e.g Pb(NO3)2+Na2SO4→PbSO4+2NaNO3,咁我點知會咁樣出?- -唔通死記?定係要睇番E.C.S個表睇下有冇O.A同R.A?但係唔係隻隻REACTION都係REDOX架WO?!同埋又好似張suphur放入去concentrated nitric acid度,會唔會出NO2呢?又點知呢?咁放入去CONCENTRATWED既HCL度又會點?有冇人知道可以點睇2種reactant放埋一起有冇反應,會出咩= =?
另外,我想問就係係d chemical eqt.度,e.g,2NaNO3咁,係咪即係有2mole既sodium?!定係即不過係一種mole ratio,唔係他們真實既mole?*v*

[H]LMT

冇記錯的話會有displacement的
類似 AB+CD→AD BC
跟番個reactivity series


(好似炸~"~ 我d chem 比番晒老師)

[ 本帖最後由 [H]LMT 於 2-9-2008 15:11 編輯 ]

＊ＥｒＩｃ＊

原帖由 [H]LMT 於 2-9-2008 15:09 發表
冇記錯的話會有displacement的
類似 AB+CD→AD BC
跟番個reactivity series


(好似炸~"~ 我d chem 比番晒老師)

但係其實displacement reaction唔係只不過系把一種metal ,列如Na咁,放入CUSO4度,會變左Na2SO4
以上只不過係一種metal既solid state放入一種metal既ionic compound既solution度出現displacement reaction
but....如果系2皇既ionic compound呢?點知他們既反龐會係點?!式者有冇reaction?

piyopiyo

Q.e.g Pb(NO3)2+Na2SO4→PbSO4+2NaNO3,咁我點知會咁樣出
A.成個solution入面有堆ion,呢堆ion係隨意咁痴,,,當Pb2+撞埋SO4 2-果度,就會變成solid...而Pb2+撞埋NO3-度就無野發生...所以反應去到最後就係Pb2+撞晒,出晒PbSO4...只剩Na+同NO3-於solution入面
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簡單一句
你問下自己係咪真係明白咩叫ion...

＊ＥｒＩｃ＊

hia_a
咁點知2種SOLUTION有冇反應...
同埋我應該幾時睇e.c.s,幾時好似用番您上邊果度咁?
另外,把SILPHUR放入CONCENTRATED既nitric acid,我點知有冇反應,又點會出d咩?睇e.c.s?sulphur冇得睇,睇書,書冇講?點知?我做ce同埋d保習d chem notes 都冇講度點解!!

＊ＥｒＩｃ＊

原帖由 ＊ＥｒＩｃ＊ 於 2-9-2008 16:08 發表
hia_a
咁點知2種SOLUTION有冇反應...
同埋我應該幾時睇e.c.s,幾時好似用番您上邊果度咁?
另外,把SILPHUR放入CONCENTRATED既nitric acid,我點知有冇反應,又點會出d咩?睇e.c.s?sulphur冇得睇,睇書,書冇講?點知?我做 ...

自1錯野,係sulphur=]

piyopiyo

原帖由 ＊ＥｒＩｃ＊ 於 2-9-2008 16:08 發表
hia_a
咁點知2種SOLUTION有冇反應...
同埋我應該幾時睇e.c.s,幾時好似用番您上邊果度咁?
另外,把SILPHUR放入CONCENTRATED既nitric acid,我點知有冇反應,又點會出d咩?睇e.c.s?sulphur冇得睇,睇書,書冇講?點知?我做 ...

1.有d要背,有d用4樓ge方法
2.在這個case sulphur係reducing agent,conc. nitric acid is reduced to form NO2 which is a reddish brown gas.

the ON of S is 0... The ON of S can vary from -2 to +6.It therefore depends on the situation in which it is an OA or RA.[[tk_36]]

[ 本帖最後由 piyopiyo 於 2-9-2008 16:37 編輯 ]

＊ＥｒＩｃ＊

thx...勁@@
另外我仲想問下列如把AgNO3拎去燒,就會DECOMPOSE成Ag(s)同NO3?==有冇錯,nitrate ions會以咩state出現,silver原本係ions,變返去solid?咁邊個食粒電子?
and then ...係        呢個過程點解要燒?燒係比energy去做reaction?定係只可以話係比一個suitable既situation,定係有咩用?- -          好抽象- -     咁呢個過程係咪release energy?如此咁講,即係話metal i變ions,去俾電子,係放energy,去become stable?咁另外咁睇,silver同no3,燒返去又變返agno3,又係比energy他們定係點?.3.

＊ＥｒＩｃ＊

原帖由 piyopiyo 於 2-9-2008 16:33 發表

1.有d要背,有d用4樓ge方法
2.在這個case sulphur係reducing agent,conc. nitric acid is reduced to form NO2 which is a reddish brown gas.

the ON of S is 0... The ON of S can vary from -2 to +6.It the ...

照您咁講即係當呢d可以ON varies既話,假如遇到OA,它就會變R.A,:遇上O.A,又變返R.A?!咁神奇?!A_A

FcTo~

原帖由 ＊ＥｒＩｃ＊ 於 2-9-2008 17:05 發表
thx...勁@@
另外我仲想問下列如把AgNO3拎去燒,就會DECOMPOSE成Ag(s)同NO3?==有冇錯,nitrate ions會以咩state出現,silver原本係ions,變返去solid?咁邊個食粒電子?
and then ...係        呢個過程點解要燒?燒係比en ...

silver係+ve ，變返solid ge時候係應該吸e- ~
我諗粒e- 應該係由NO3- 度吸番ge~
burning係想比energy呢個compound去react，所有reaction都要有個activation energy去推動~
有錯請指~
thx~