|
More site info...
|
|
Forum profile page for 科學問題區 on http://www24.discuss.com.hk.
This report page is the aggregated overview from a single forum: 科學問題區, located on the Message Board at http://www24.discuss.com.hk.
This forum profile page summarizes the general forum statistics such as: Users Activity, Forum Activity, and Top Authors, which are reported in either a table or graph below for a given reporting time period.
Additional forum profile information for "科學問題區" on the Message Board at http://www24.discuss.com.hk is also shown in the following ways:
1) Latest Active Threads
2) Hot Threads for Last Week
Warning: These statistics are generated using 'best efforts' and can experience delays and reporting errors at times. Please note that such statistics do not constitute a forum's popularity and/or exact posting volumes at any given reporting period.
|
|
|
|
|
Posting activity on 科學問題區:
|
|
Week
|
Month
|
3 Months
|
|
Threads:
|
119
|
364
|
976
|
|
Post:
|
218
|
644
|
2,032
|
|
|
科學問題區 Posting activity graph:
|
Top authors during last week:
user's latest post:
screening effect 同electronic...
Published (2009-12-15 08:22:00)
回覆 1# 的帖子 These two effects are different in nature. The screening effect is the reduction of nuclear charge experienced by the valence electrons due to the inner-core electrons. The electron-electron repulsion, on the other hand, is the electrostatic interaction between two electrons (or more) when they come close to each other.
user's latest post:
點解酒放得愈耐愈醇?
Published (2009-12-12 23:15:00)
I guess there are different types of bacteria and they may produce different types of organic products
user's latest post:
問 bio 1995 pastpaper
Published (2009-12-13 19:39:00)
[按此打開] [隱藏] CO2都係acidic gas 所以雨水本身都係有少少acidic 但係H2CO3係weak acid H2SO4同HNO3就係Strong acid,所以會enhance acid rain 其實e+好多pollution problem都係enhanced左先會有害 例如greenhouse effect咁,冇左佢地球既溫度會低到住唔到人 熱門搜尋: account acca accounting ballet class
user's latest post:
salt bridge鹽橋
Published (2009-12-13 14:48:00)
回覆 2# 的帖子 salt bridge關咩melting pt事呀= =" allow ions to move from one half cell to the other to complete the circuit 係因為係個experiment個到,兩個half cell係分開咖...所以未唔通電囉, 個salt bridge係可以放d ion出黎,令到佢有電子既流動....(因為ion帶極咖)
user's latest post:
死啦,唔色做tas,來幫幫我
Published (2009-12-12 18:49:00)
[按此打開] [隱藏] 推推推!!!!!!!!!!!!!!!!!
user's latest post:
F.4 Phy Mechanics
Published (2009-12-12 17:11:00)
咁有friction 又會變成點啊?
user's latest post:
為什麼南極在冬季時氣...
Published (2009-12-15 13:35:00)
不太清楚，不過可以向深海環流的方向去想 熱門搜尋: men's skincare mts mts 微針療法 plastic surgery
user's latest post:
gamma ray vs X-ray
Published (2009-12-10 09:35:00)
引用: 原帖由 jmlo 於 2009-12-10 09:26 AM 發表 No, I don't think so. Assume that frequency is the only parameter you know about the photon. It is impossible to tell whether it comes from a gamma radiation or X-ray radiation. Thanks. So they are identical? If a question asks me to tell the difference between gamma and X-ray of same frequency, what should I say? 熱門搜尋: 艾灸 沙田美容院 禿髮 永久脫毛 穴位按摩
user's latest post:
問 bio 1995 pastpaper
Published (2009-12-13 01:30:00)
引用: 原帖由 lskcwilson 於 2009-12-13 12:56 AM 發表 得SO2係ACIDIC GAS,WHICH DAMAGES STONE BUILDINGS AND FORESTS 用d non-purified coal就會出SO2 因為有S CO2都係acidic gas bor,,點解CO2唔得? 熱門搜尋: 報稅 速遞 貨運 陳列架 陳列貨架
user's latest post:
電場
Published (2009-12-13 17:44:00)
電場 [按此打開] [隱藏] [ 本帖最後由 Stevefeifei 於 2009-12-13 06:33 PM 編輯 ] 熱門搜尋: mts 微針 dance hair loss beauty centre fitness center fitness equipment
|
|
|
|
Latest active threads on 科學問題區::
Started 1 week, 5 days ago (2009-12-06 01:23:00)
by AngelPaul026
為什麼南極在冬季時氣溫還會冷過北極的嗎？
[按此打開]
[隱藏]
有沒有人解答為什麼南極在冬季時氣溫還會冷過北極的嗎？如果有的話，可否回答的嗎？ 熱門搜尋: 搬寫字樓 會計 會計服務 會計師 會計員 運輸
Started 2 weeks ago (2009-12-03 13:25:00)
by 黃大仙
你可以咁睇:
輸入功率 ( 電 ) = V I
而摩打的輸出有 1. 動能 2. 熱能 3. 其他如聲音(極少量，可不計)
而熱功率是 I VR.
Back emf = V - VR
因此 VB I = 機械功率 熱門搜尋: 樓宇按揭 貸款 credit report
Started 3 days, 4 hours ago (2009-12-15 08:22:00)
by jmlo
回覆 1# 的帖子
These two effects are different in nature.
The screening effect is the reduction of nuclear charge experienced by the valence electrons due to the inner-core electrons.
The electron-electron repulsion, on the other hand, is the electrostatic interaction between two electrons (...
Started 3 days, 5 hours ago (2009-12-15 07:52:00)
by pkhk00000
Started 3 days, 18 hours ago (2009-12-14 18:52:00)
by 靜止
Started 3 days, 20 hours ago (2009-12-14 16:04:00)
by MichaelOwen
打埋個procedure俾大家參考下 thx
A. Reaction of Cyclohexene with bromine
1. Measure the mass of a clean boiling tube and the cork.
2. Using the measuring cylinder in the fume cupbroad, measure 25 cm^3 of the solution of bromine in volasil into the boiling tube. Cork it immediately.
3. Measure the mass of the tube with the cork and ...
Started 4 days, 2 hours ago (2009-12-14 10:07:00)
by jmlo
回覆 1# 的帖子
Molar mass of Al2(SO4)3 = 342.15 g/mol
Mass of Al2(SO4)3 = 22 g
# mol Al2(SO4)3 = 0.0643 mol
# atoms in Al2(SO4)3 = 17
# atoms in 22g Al2(SO4)3 = 0.0643*17*6.022 x 10^23 = 6.58 x 10^23 atoms 熱門搜尋: packing bag pallet pallets plastic plastic bag ...
|
|
Hot threads for last week on 科學問題區::
Started 1 week, 1 day ago (2009-12-10 09:16:00)
by [K]ProStaff88
gamma ray vs X-ray
[按此打開]
[隱藏]
If a photon is of a frequency between gamma and X, can I distinguish between them? 熱門搜尋: 報稅 速遞
Started 1 week ago (2009-12-10 14:04:00)
by jmlo
回覆 1# 的帖子
(1) 1.32% , 0.948% 和 13.2% 各是哪種醋酸溶液的電離度?
----> 0.948% (0.2M), 1.32% (0.1M), 13.2% (0.001M)
(2) 上述三種溶液的H+ 的濃度各是多少?
----> 0.2M HOAc: [H+] = 0.0019M
----> 0.1M HOAc: [H+] = 0.0013M
----> 0.001M HOAc: [H+] = 0.000125M
(3)上述三種溶液哪種導電性最強?
----> 0.001M HOAc has the highest ...
Started 1 week, 2 days ago (2009-12-08 21:58:00)
by nola
Started 6 days, 15 hours ago (2009-12-11 21:48:00)
by ktmc333
who can help me...plz..thx
a
lot 熱門搜尋: barcode barcode printer barcode printing booth design branding agency
Started 1 week ago (2009-12-10 18:26:00)
by ch2008113259
有D formula mass既問題
[按此打開]
[隱藏]
hydrogen既mass number係1,atomic number係1,同deuterium既mass number係2,atomic number係1。咁叫你找D2O,姐係deuterium同oxygen react既product。咁叫你找佢d formula mass。咁唔係要拎佢既relative atomic mass計咩,但其實係用咩黎計??唔該幫幫手。(O=16.0) 熱門搜尋: 彩光 排毒 產後瘦身 產後調理...
Started 1 week, 1 day ago (2009-12-10 00:24:00)
by lihonling
死啦,唔色做tas,來幫幫我
[按此打開]
[隱藏]
Determination of the Concentration of Chloride and Hydroxide ions in a Solution
Why is the experiment performed as soon as possible ?
2. In step 3, what is the function of nitric acid ?
3. In step 3, what is the function of ...
Started 5 days, 23 hours ago (2009-12-12 13:36:00)
by arsc
more different types of sugars as products of fermentation 熱門搜尋: men's skincare mts
Started 5 days, 22 hours ago (2009-12-12 14:47:00)
by jmlo
回覆 1# 的帖子
Note that KE = hf - W, where W is the work function of the metal. Now, if f is doubled, then the new KE is:
KE' = h(2f) - W = 2hf - W = hf + (hf - W) = hf + KE
Since hf > KE, we know that KE' > 2*KE. Hence, the new maximum KE of the ejected electrons is not doubled but larger....
Started 1 week, 2 days ago (2009-12-09 08:45:00)
by jmlo
回覆 1# 的帖子
In this example, we can tell right away that Cl2 does not have a giant covalent molecular structure. It is a simple molecule. When you look at Cl atoms in Cl2, each of them has 3 lone pairs and 1 bond pair. Therefore, one covalent bond is enough to make them have an octet configuration....
Started 5 days, 12 hours ago (2009-12-13 00:56:00)
by lskcwilson
得SO2係ACIDIC GAS,WHICH DAMAGES STONE BUILDINGS AND FORESTS
用d non- purified coal就會出SO2
因為有S
|
|
Size: 2,886 bytes
