化學

BaCl2+CuSO4→BaSO4『↓』+CuCl2
C2H5OH+3O2→2CO2『↑』+3H2O
請問有人知道『 』中的箭頭代表的是什麼意思嘛
知道的人麻煩幫解答一下，謝哩~!!

2006-12-27 14:49:13 · 1 個解答 · 發問者 筱涵Lin 2

一 . 35克的食鹽 ( NaCI=58.5 ) 溶於水形成了 150 克的水溶液，問此鹽水的重量百分率濃度若干 ?

二 . 35克的葡萄糖 ( C6H12O6 )溶於 150 克水形成水溶液，問此糖水的重量百分率濃度若干?

三 . 欲配製 2M 的 Na2CO3 水溶液 250 ml 則需取 Na2CO3 若干克溶於水形成250 ml 水溶液 ? ( Na2CO3=106 )

那位大大幫忙解算~謝謝 !

2006-12-27 12:07:44 · 2 個解答 · 發問者 James 3

請問鹽酸(清洗廁所用)加漂白水會產生什麼化學反應？
聽說這兩種家中常見的化學物質不能加在一起，
那麼加在一起到底會怎樣呢？

2006-12-27 09:40:29 · 6 個解答 · 發問者 ? 7

Q1: 除O2外,N2O也可使有餘盡的木條重燃嗎?(IF CAN"T,仲有咩可使有餘盡的木條重燃?)
Q2:Br2可使濕KI澱粉試紙轉藍黑色?

2006-12-26 20:09:54 · 1 個解答 · 發問者 unoldman2000 1

4-pyridylurea翻譯成中文是什麼阿？？
一直查不到...
作翻譯作業要的

2006-12-26 19:57:47 · 1 個解答 · 發問者 Anonymous

Resorcinol
O-Cymen-5-01
Salvia Officinalis(Sage)Leaf Extract
Glycin Soja (Soybean) Protein
Sodium Citrate
Serine
Sacchride Isomerate
Placental Protein
Glycolic Acid
Methylparaben
Sodium Cocoyl Isethionate
Sodium Cocoyl Glutamate
Myristoyl Glutamate
Microcrystalline Cellulose
Hydrolyzed Wheat Flour
Papain
Aloe Barbadensis Leaf Juice
Sodium PCA
Benzethonium Chloride

2006-12-26 19:48:54 · 1 個解答 · 發問者 卉卉 1

我想問 optically active , chiral , racemic 之間有mud關係....plz help me...

2006-12-26 18:02:17 · 2 個解答 · 發問者 Anonymous

題目是這樣

將存氫氧化鈉晶體2克,投入一未知濃度的硫酸水溶液25毫升中,恰好中和,則硫酸當量濃度為何?(原子量:Na=23,O=16,H=1)

答案:是2n

我想要知道 她的計算方法 還有公式

越詳細越好 拜託拜託

還有解釋一下 什麼 ~克式量~ 電子轉移數目 ~克當量 ~當量數~

分別在題目中是哪些 數據

拜託一下 各位化學達人

2006-12-26 17:57:37 · 2 個解答 · 發問者 小智 2

以下的 statement 對嗎?
1) Covalent compound 不是屬於 simple molecular structure 就是屬於 giant covalent structure.
2) 所有 ionic compound 都屬於 giant ionic structure.
3) 所有 metal 都屬於 giant metallic structure.

唔該晒大家~~

2006-12-26 17:37:33 · 1 個解答 · 發問者 Savio　 4

1-butylcarbamoyl-2-benzimidone

這是什麼啊??

希望快點回答我...

報告要用的!!!!

2006-12-26 16:21:58 · 1 個解答 · 發問者 kinyi 4

我想問在 paper chromatography 上的係 element 定係幾隻色的compound定係幾隻色的mixture

2006-12-26 15:32:23 · 2 個解答 · 發問者 ? 2

1st statement:
Pure sulphuric acid is strong acid.
2nd
Pure sulphuric acid completely ionizes in water.

Why both statements are WRONG?

2006-12-26 15:31:28 · 2 個解答 · 發問者 2003 2

以下邊個組合是對的 ?
釋出氣體 生成溶液的顏色
A 二氧化硫 淺黃
B 二氧化硫 黃


答案係邊一個組合~~~~~~~
請解釋~

2006-12-26 13:23:47 · 1 個解答 · 發問者 ckt_hide 2

UV消光膜 MTC19
(請提供英文化學名稱)

1)聚丙烯(PP)
2)聚乙烯(PE)
3)芥酸酰胺類
4)二氧化硅(SiO2)

thanks!!

2006-12-26 11:47:08 · 4 個解答 · 發問者 Waiiki 1

1.Why the burette and pieptte should be washed with distilled water and the solution to be used but NOT the solution to be used and then distilled water?

2.Why the volumetric flask should be washed with distilled water only but NOT the solution to be used?
I think the no. of mole of the solution will be affected
as the total volume in volumetric flask remain unchanged(i.e 250cm³)
so why cannot wash with the solution to be used?

2006-12-26 05:37:33 · 1 個解答 · 發問者 2003 2

麻煩各位大哥

跟我講解一下多結晶矽太陽能電池的製程

還有非結晶矽太陽能電池的製程吧!!

報告用的 只缺製程這部份了

謝了

2006-12-25 21:37:12 · 4 個解答 · 發問者 胤 1

在以下情況應用甲基橙還是酚酞指示劑去測試?同埋點解要加果隻指示劑??
1,在強酸加強鹼.
2,在強酸加弱鹼.
3.在弱酸加強鹼.

2006-12-25 19:25:41 · 2 個解答 · 發問者 pui shing 2

二氧五圜(1,3-Dioxolane
碘化鉀
氫氧化鉀
誰有以上物質安全資料表

2006-12-25 17:57:10 · 1 個解答 · 發問者 dida 1

我想問下點解做anodization果時要用一卷aluminium sheet 做cathode,果卷野又要圍住個anode??

2006-12-25 16:36:21 · 1 個解答 · 發問者 Anonymous

浮射線是我的負擔
在某些場所有浮射線怕用壞眼睛
所以請問誰可以給我解答
聽說炭可以

2006-12-25 15:10:18 · 3 個解答 · 發問者 Anonymous

解釋名詞或簡答題：
(a) the first law of thermodynamics
(b) state function of thermodynamics
寫出以下電池所使用的oxidant 是什麼？及此oxidant 所參與之half reaction。
(c) mercury battery
(d) hydrogen-oxygen fuel cell

2006-12-25 14:25:02 · 1 個解答 · 發問者 奇峰 1

Is sulphuric acid a bleaching agent??? If yes, why???

thx a lot

2006-12-25 13:48:12 · 3 個解答 · 發問者 tse 1

Nucifera
lsethionates
Docosahexaenoic
cis
superfatted
polyglycerin
diglycerides
monoglycerides
Isosorbide
nonvolatility
lmidazoline
lnorganic
Octachlorohydrate
electroneutrality
stoichiometrically
lnorganic
Isethionic
Dinitrophenol
diglyceride
Homopolymeric
cosolvents
homopolymers
Decaoleate
properties

2006-12-25 12:56:45 · 1 個解答 · 發問者 企鵝小朋友 1

A commercial ammonia called "0.68ammonia "has a density of 0.68gcm^-3 and contains approximately 34% of ammonia by mass.
a)Calculate the mass of ammonia present in 1dm^3 of the solution of this commercial ammonia.
b)Calculate the molarity of this solution.
c)Calculate the volume of distilled water added if the solution has to be diluted to 1mol dm^-3.

2006-12-25 09:38:43 · 1 個解答 · 發問者 guaeiogaeighi 1

A sample of concentrated sulphuric acid has a density of 1.83gcm^-3 and contains 94.0% of sulphuric acid by mass .What is the concentration of sulphuric acid in the sample?
(Relative atomic masses:H=1.0,O=16.0,S=32.1)

2006-12-25 09:28:27 · 1 個解答 · 發問者 guaeiogaeighi 1

I have done an expt by mixing some chemicals

result:
mixture:trichloromethane+ethyl ethanoate
---exothermic
mixture:ethanol+cyclohexane
---endothermic

Explain the observed temp. change on mixing trichloromethane & ethyl ethanoate as well as ethanol & cyclohexane in terms of the interactions between the molecules.

I don't know how to ans it.

2006-12-25 09:12:19 · 2 個解答 · 發問者 CT 2

The mass of hot soup is 0.3 kg . The specific heat capacity and temperature of the soup are 3600 J kg-1'C-1 and 90'C respectively . How much water at 2'C should be added to lower the temperature of the soup to 30'C ?

2006-12-25 08:40:00 · 3 個解答 · 發問者 怡文 1

A heater is used to heat 3 kg of aluminium for 4 minutes . The rise in the temperature of aluminium is 30'C . If only 80% of the energy supplied by the heater is transferred to aluminium , find the power of the heater . The specific heat capacity of aluminium is 900J kg-1 'C-1 .

2006-12-25 08:28:51 · 2 個解答 · 發問者 怡文 1

In an experiment ,1.00M sodium hydroxide solution was added to 25.0cm^3 of 1.00M sulphuric acid until the acid was completely neutralized.What is the concentration of sodium sulphate in the resulting solution?

2006-12-25 08:17:08 · 1 個解答 · 發問者 guaeiogaeighi 1

what is the rate of hydrolyzed ?
why a tertiary carbocation 的rate of hydrolyzed快過 secondary carbocation?

2006-12-25 05:10:51 · 1 個解答 · 發問者 Anonymous