Thursday 28 May 2009

Chemistry – bonding (Ionic and covalent bond)

(I can't show the chemical formula properly here, but it should be right in the download version.) (sorry for stupid mistakes before... edited) 1) Elements combine and form compounds, holding together by chemical bonds, which is a force that holds atoms together. 2) Atoms become stable when their electronic arrangements are same as noble gases, and so that the aim of forming bonds is to let atoms contain electronic arrangements like noble gases. (or fully filled the outermost electron shell.) 3) Ionic bonds form when metallic atoms combine with non-metallic atoms, and covalent bonds forms between non-metallic atoms. 4) Ions are electrically charged particles, and form when atom loss or gain electrons. Group 1,2,3,6,7 have +, 2+, 3+, - and 2- charge respectively because losing or gaining such number of electrons make them become stable. The number and position of protons and neutrons don’t change. 5) Cation (positive ion) usually forms among metals because they loss electrons to contain the noble gas electronic configuration. e.g. Na→Na++e- 6) Anion (negative ion) usually forms among non-metals because they gain electrons to contain the noble gas electronic configuration. e.g. Cl+e-→Cl- 7) Ionic bond is the strong non-directional electrostatic force of attraction between oppositely charged (cation & anion) ions. When ionic bond is formed, there’s a complete transfer of electrons from metal to non-metal atom. In Chemical formula, the metals always go first in ionic bond. e.g. Na+ (a cation)+Cl-(a anion)→NaCl e.g.2 Mg2+(a 2+ charged ion)+2F-→MgF2 8) Some ions are polyatomic ions formed by covalent bond, and some metals have different oxidation numbers will have different number of charge. For example, Iron(III) is 3+ charged but iron(II) is 2+ charged. 9) Formulae of ionic compounds show the type of different ions present and ratio of ions of compound. Since the ionic compounds are electrically neutral, so that the total positive charge must be equal to the total negative charge. 10) A way to calculate the ratio between ions is to compare their charge. For example there’re two ions, with a+ and b- charge, the ratio will be b:a (assume this is the simplest form, otherwise simplify it first.) such that the positive charge (ab+) and negative charge (ab-) are equal. 11) If some ions are polyatomic ions and their ratio isn’t 1, use a bracket to show that “two times of the whole ion”. e.g.: we use Mg(OH)2 instead of MgOH2 or MgO2H2. 12) The naming of ionic compounds – Simply cation come first, then anion. The bracket after metal (e.g. Iron(II)) is also needed. Simple non-metal anions end with –ide, polyatomic ions which contain oxygen end with –ate or –ite, which –ate contains more oxygen. (e.g. SO4 is sulphate and SO3 is sulphite.) 13) Covalent bond is the strong directional electrostatic force of attraction between the shared electrons (negative) and the two nuclei (positive). 14) Covalent bond involves sharing of electrons instead of complete transfer of electrons, and they are found among non-metals. Molecule is formed when two or more atoms combined together by covalent bond only. The pairs of electrons shared between two atoms are called bond pair electrons. For example, H2 is formed by covalent bond (but this is still considered as “element”), they shared their electrons, and the outermost electron shell of both Hydrogen is fully filled. The bond pair can be expressed by H-H. Each hydrogen atoms forms H2 and forms diatomic molecule. The formula of covalent compounds is also called molecular formula. The molecular formula of a substance gives the actual number of atoms of each element in each molecule of the substance. 15) There’s a double bond formed in oxygen, and they shared 2 pairs of electrons. The pairs of electrons in the outermost shell and not involved in sharing are called lone pair electrons. Double bond is represented by O=O. Triple bond formed in nitrogen can be represented by N≡N. Two hydrogen and one oxygen combine together to become H2O, and it can be expressed as H-O-H. Further examples include CO2: O=C=C and H2O2 (hydrogen peroxide) H-O-O-H. 16) Formulae of covalent compounds – First, calculate the numbers of electrons needed to fill the outermost electron shell. Then found the ratio just like ionic bond. The formula just shows the amount and species of elements shown. For example, the molecular formula of H-S-H is H2S. 17) Note that this way of calculating ratio is just one of the ways to make covalent bonds. There maybe different types of covalent bonds form by the same type of elements. For example, hydrogen and oxygen can form H2O and H2O2. 18) The relative molecular mass and formula mass equal to the sum of atomic masses of all atoms present in the molecule of that substance or in the formula unit of it, but relative molecular mass can be only applied onto molecule. For example, molecular mass of H2O = mass of 2 H + mass of O = 18

Sunday 24 May 2009

Geography - the rich and the poor

(Download version avilable for this post!) Geography – the rich and the poor There are varies degrees of wealth of country existing in this world and it depends on how they’re developed. Countries can be classified into more developed countries (MDCs) and less developed countries (LDCs). Here are the following indicators: 1) Gross National Income per capita (GNI per capita) refers to GNI divides by the total population of the country. It gives the average income of a people in a country, and can accurately measure how rich is the people in that country averagely, therefore it’s useful for comparison among countries. (more than US$9266→MDCS, otherwise LDCs.) 2) Urbanization level – percentage of urban population in the country, higher percentage means higher urbanization level. (MDCs have a higher %.) 3) Life expectancy give out the expected average years that a people can live in that country, and shows the general health condition and quality of medicine service in that country. (MDCs’ life expectancy is higher.) 4) Age structure shows no. of population in different age groups in that country, (MDCs → lower birth and death rate, and smaller proportion in younger people.) 5) Literacy rate -- the percentage of people which can write and read (basically) in that country, and this reflects the general education level of the country. (MDCs↑) 6) Food consumption – measured by per capita daily calories intake. MDCs have higher food consumption than LDCs, and most people in LDCs suffer from hunger and malnutrition. 7) Energy consumption shows the living standard and industrial level of the country, MDCs’ energy consumption is much higher because of their high living standard and industrial level. We can roughly draw a line to classify the “Rich North” and the “Poor South”, Rich North includes MDCs such as US, Canada, European countries, and Australia (but it’s in the South hemisphere). Poor South includes China, Africa, but also HK (although HK should be more developed.) Some countries are wealthier because of the following reasons: 1) Resources – it’s very important for making useful products (for example, curde oil→plastics) and making energy. Countries which have more natural resources are usually richer, because they can use their resources to make many things to earn money, and those surplus resources can again sell into money. 2) Technology level – this affect the speed of development in the country. In MDCs, government and enterprises is willing to invest to do researches and improve the technology, this can improve the agricultural and industrial productivity (better qualities and higher quantity) and bring them more money, the surplus commodities can also bring them foreign exchange. 3) Population growth – the triangular-shaped population structure for LDCs hinders their development, because their high birth rate and decreasing death rate bring them a high population growth, then resources for each people become less, and this will slower the speed of development for LDCs. (The population structure of MDCs is bell-shaped, and they have both low birth and death rate.) 4) Political stability is important for a country to development. Corruption and change of government (abnormally) happens frequently in the LDCs, and damage the well-being of people and the economic development. But all humans are equal and should have human rights; therefore we should help those LDCs. The following is what those MDCs can help the LDCs: 1) Emergency relief – MDCs provides food, medicines and clothing to LDCs if they encounter with natural disaster or war. Some organizations such as Oxfam, the Red Cross and World Vision also provides these emergency relieves. 2) Loans is a common form of aids to LDCs. Many governments and organizations such as World Bank provide loans to them. They use those loans to solve their financial problems and to build large facilities such as dam, railways and estates. 3) Transference of technology -- The technology level of LDCs is low, so that MDCs provide technology and machinery to them, and give them technical assistance to them. All these can improve the productivity of LDCs. 4) Develop long-term projects such as improving infrastructure, farming methods, education and children health can also help them. Some countries or organizations assist or provide loan to them to complete such projects. But sometime those aids can’t help the LDCs because of some reasons. The corruption among government or warfare blocks the aids from people in need; some MDCs want to control those LDCs through aids so that LDCs may refuse to receive aids, and some transference of technology is restricted because of some reasons. On another way, those LDCs can’t rely on those short-term aids, and some poorly panned aids can’t help LDCs properly. Therefore, the best way to help them is to encourage them to self-help. MDCs improves their education and nutrition level to let them can self-help in long-term. Also, MDCs start to consider local needs instead of money-only helping in recent years. They try to design development programme that local people can accept and manage, this can ensure the progress of the plan. To protect local industries, they impose import restrictions such as tariffs and import quotas. As a result, LDCs can only import primary commodities to MDCs such as agricultural products and their income is low, and they can benefits from international trade. Some organizations put force on the MDCs to make them to remove the trade restrictions so they have a fair trade relationship and they can benefits from it.

Thursday 21 May 2009

Physics notes– total internal reflection

Total internal reflection By Shell's Law, we know that the value of sin x can't be larger than 1. But if one side of the equation is larger than the refractive index on another side, we'll found that another side of the equation can never equal to another side, and the total internal reflection occur. It's a “reflection” so that it obeys the law of reflection. For example, the light strike from glass (R.I. 1.7) to air, 1.7sin (angle of incidence) =1sin (angle of refraction), if the angle of incidence is big enough, equation can’t hold. The “big enough” limit is called the critical angle, and c=sin^-1 (1/x). It follows that when the R.I. is bigger, critical angle is smaller and total internal reflection is easier to happen. This explained why it mostly happen in medium with higher R.I.. Applications: 1) Views under water – when you're under water, you may not see the image above water if the angle of incidence is big enough, and the range that you can see image above water is in cone shape, with the axis from your eyes, perpendicular to the water surface. (This is because the angle of incidence is limited.) 2) Periscope – If we use glass with enough big R.I.(bigger than 1.5, usually, is enough), we can make two 45-90-45 triangular prisms to reflect light just like plane mirrors. 3) Diamond – it's so bright because it's R.I. is too high (above 2) such that all light (especially after process) will be reflected back. 4) “Cat's eye” in front of the car uses the same rule to give out strong light. Optical fibres Optical fibre is a tube-like device which can transmit light. It's made by glass and some other material, layer by layer. Since total internal reflection always occur inside the tube, and the tube can be bent into a certain angle, it can transmit light in the curved path. There is various application of optical fibre. The most important use is the usage on telecommunication services. Comparing with the traditional wire, it's much cheaper since the traditional wire uses a lot of copper. Even the material cost is more expensive than the production cost of optical fibre considering the same volume. Another important use is endoscope for surgery. ->"optical fibre" as extention reading , here!

History notes - From Japanese occupation to being as an IFC

(This is just part of the topic "Hong Kong on 20th century". The remaining part of this topic, "popular culture" and "relationship with China" will be posted later.) Hong Kong in the 20th century Japanese occupation Since 1930s, Japan was ruled by militarists and they plan to expand her land, and they adopted the expansionist policy. During WWII, on 8th Dec, 1941, Japan attacks Pearl Harbor, an American naval base, and Hong Kong at the same day. They bombed Kai Tak airport, NT, Kowloon and occupied Kowloon Peninsula in only 6 days, and at Christmas of that year, the governor of Hong Kong at that time, Sir Mark Young surrounded. Then a military government(HSBC as Government House) was set up to rule Hong Kong, and they adopted the following policies: 1) The Repatriation of the Chinese – sending all jobless/homeless people back to China and young people to Japan to work. 2) Food rationing – Based on food shortage during war, a system of food rationing is adopted on 1942; nesscities like rice, flour, and salt were all rationed. As a result, many people suffered from malnutrition. 3) Currency – In order to raise money, Japan issued military yen and later became the only circulate currency in Hong Kong. The HK dollar being exchanged is use for buying supply for Japan (because HK dollar is valuable round the world), after Japan surrounded on 1945, they became worthless and Japan refused to change them back into HK dollar until now. 4) Education and culture – they imposed tight control on mass media and textbooks, compulsorily teach Japanese in schools, Japanese festival celebrated and name of roads were changed. The hygiene conditions that time were poor. Damaged roads, pipes weren’t repaired, garbage piled up and cholera broke out. Anti-Epidemic Bureau was set up but not successfully improves the condition. After Japan’s surrounding on 15th August, 1945, Sir Cecil Harcourt came HK and restore British Control. Sir Mark Young restores the civil government on April, 1946. After the war, military yen is replaced by HK dollar, control the distribution and prices of food, rebuilt facilities, all those were carried out by Sir Cecil Harcourt. The Young plan – Sir Mark Young wanted to set up a municipal council, and proposed the Young Plan, but it’s finally dropped in 1952. From Entrepot to IFC 1) From post war to the formation of PRC, civil war was broken out in China and lots of people escaped to HK, and bring capital, skills and cheap labour force, this made HK possible to change into an industrial center. 2) Korean War (1950-1953) – United Nations placed embargo on Chinese good based on different blocs, and HK’s re-export trading decreased sharply, and HK had to find a new way to earn money, and that’s industry. 3) 1950s-mid-1970s – during this period, industries in HK are labour-intensive and mainly light industry, such as textile, clothing, plastics, electronics, watches and toys. However later on, some Asian competitors came out and protectionism grew in Europe and US, and HK began to diversify towards the production of better goods. 4) 1980s- HK’s economy went to a process of diversification and Financial services, and tourism is developed, transportation and communication is improved and HK became an international financial center. Livings of people in HK from 1950s to 1980s Housing: 1950s squatter huts, 1953 – Shek Kip Mei fire→resettlement estates 1960s Low cost housing estates for low income families 1972 redevelop old housing estate 1978 House Ownership Scheme (HOS) Education: 1950s Primary educationExpanded; Compulsory primary education 1960s All children under 15 must receive 9 years free compulsory education 1970s Set up technical and prevocational schools before the end of 20th century : 7 universites already Social welfare: Voluntary organization before WWII: Tung Wah group of Hospitals, Po Leung Kuk after WWII: the Caritas of HK, Hong Kong Red Cross, The community Chess 1948 Social Welfare Office→Department of Social WelfareProvide family and child welfare services, and cash allowances to elderly and disabled. The rapid growth of economy → create many job opportunities, raised income level of people in HK, create a better environment.Everyone began to have a home and children receive education, and live standard has improved continually.

Sunday 17 May 2009

Carol的一萬字~Part 10(I)

實地試了一下,大埔可以分水陸兩路踩上粉嶺的 粉嶺公路也不太難~~ =================================== 當我還想慢慢觀想這個超豪華運動場,然後概嘆這個隱形富豪時,我還是被她拉進運動場裡去。 從外面上半部的玻璃幕牆看進去,那是個運動場無疑;但真真正正走進去,卻會發現更多設施,跑步機等都一應俱全,與其說是一個運動場,不如說是訓練運動員的工廠,那些設施太厲害了。 運動場中央的單車賽道閃著幾個騎著單車的身影,似在互相較量,一時三刻也別想停下來。只是──「你們都給我停下來啊啊啊啊~~」少女以足以震破耳膜的聲音吼道,我敢肯定那絕對是吼出來的,因為我反射性地蓋著耳朵退後了N步,然後裁在一堆BMX中,儘管三棱八角的BMX把我刺到痛得厲害,我還是沒法掙扎爬起來,明顯地被嚇倒了。 「你沒事吧?」驚奇的聲音從上方傳來,我這才悠悠醒過來,但背脊還是痛得要命,依乎還在流血。 少女身旁多了幾個人,有男有女,共通點是年紀差不多,而且無論男女都那麼好看、迷人。被扶起後我還得靠牆倚著,看來還傷得不輕…… 「他就是笨簡推介的人?不會吧……」 「怎麼會連紫欣的噪音也受不到,真是的……」 面對這樣的批評我簡直哭笑不得,那個看來叫做紫欣的少女彷彿前兩句不存在一樣,笑吟吟地道:「笨簡,這個新成員資質還不錯吧?」 「簡大哥」皺著眉頭道:「嗯,不錯……很被嚇到證明他的反應能力有待進步。」 千奇百怪的建築,千奇百怪的隊員。但願我不是被騙進了瘋人院。

Saturday 9 May 2009

Carol的一萬字~Part 9

被她拖著一直走,走進一個村屋群中。這群村屋跟普通的差不多,都是一座座三層洋房,落地玻璃上貼了過時的揮春對聯。雖然看起來很殘舊,但是一看就會發現裡面散發著時尚的氣息:其中一間裡甚至貼滿了歌星海報,另外,這個村屋群很新淨,建成絕不超過半年。 「這裡怎……怎麼會有這麼新的村屋?」我的記憶告訴我這裡應該是建成年數至少是雙位數的了。 「你猜猜看。」少女並沒有停下來,我們又行了大概半小時,直到一個「政府土地」的字樣的牌。奇怪的是,沒有障礙物阻止遊人進入「政府土地」!更奇怪的是,少女看到「政府土地」牌後,居然點了點頭,繞過牌子走過去! 「喂喂,進入政府土地是犯法的哦。」 少女歎氣,「唉,如果不弄個牌子弄在門口,恐怕這裡早就變成堆填區了。」 原來,自從政府實施「污者自負」後,裝修公司為了省錢,將廢料傾倒於新界私人土地中傾倒建築廢廢物,大煞風景外也造成環境污染,民不聊生──只有政府土地,他們不能動手腳。 進入「政府土地」的綠茵草地,又走了一會,竟然又回到村屋群,只不過,現在我們已經身處村屋群當中了。原來村屋包圍著的,是個巨型運動場。當我第一眼看到這個運動場時,實在很難把它描述出來:一個標準的單車賽道,各式各樣的平衡木,還有各式各樣的單車,從爬山單車、BMX到普通單車都有──當然,不包括四輪和三輪車。 我忽然覺得,香港那麼多隱形富豪,當中一定有個變態單車狂建成這堆東西給自己用。 後來,我才知道我猜對了大半。

Thursday 7 May 2009


凌晨四點九。 裁判的黑哨響起時,心,完全碎掉 一個只吹過10場歐冠比賽,有前科的黑哨來吹?笑死人 十四射一中的巴塞叫進攻足球?可恥 六粒十二碼唔俾,唔應該比的紅牌又比?正黑哨 英國足球太勁唔得?正F**KING DISGRACE!! 我冇話可說。 車仔壓著巴塞打,是事實。 不想評論這個害我浪費5小時兼失眠,令歐冠失色的罪人 唯一值得安慰的是,全世界把予頭指向那個吹成歐冠54年來最醜聞的裁判 車、曼、利、阿、塞迷如是,爭取公理! 可憐的肥丁,你已經很節制了 波歷克、杜奧巴,我們不怪你 車仔的命運... 05年-俾個無入的波踢出局...... 06年-俾個具爭議性的紅牌踢出局...... 07年-射十二碼輸左再俾利記踢出局...... 08年-圍攻不成,決賽十二碼戲劇性輸埋俾曼聯...... 09年-6粒12碼都冇 ======================== 歐冠54年最醜陋一幕! 是誰在阻擋車路士會師曼聯 ...全場比賽進行到了第95分鐘,波歷克在禁區內射門打在凱塔的手臂上,但客觀的說,這球與比基的那個故意手球完全不同,而是被動手球。本場一直不肯給車路士12碼的赫寧當然也就沒吹12碼。波歷克追著赫寧大聲咆哮,他知道,這有可能是他職業生涯中最後一次打進歐冠決賽的機會了,但這可能的最後一次,還是被挪威裁判赫寧給活生生的剝奪了。或許英超實在過於強勢,連續3個賽季都有3支球隊殺入四強,連續5個賽季都有球隊殺進決賽;而車路士晉級後,難免會出現決賽審美疲勞,這很不利於歐足聯的商業開發,因此,赫寧難免受到了他的上層的授意。或許,對於車路士來說,他們的出局是一種必然。因為很簡單,柏天尼和他的歐足聯,不希望看到車路士和曼聯再次相聚決賽。 從16強抽籤開始,柏天尼就為英超球隊設置障礙,車路士vs祖雲達斯、羅馬vs阿仙奴、曼聯vs國米、利物浦vs皇馬,明眼人都會知道為何偏偏英超這麼巧,都抽到了歐洲強隊。但令柏天尼們始料不及的是,英超球隊竟然全線飄紅,意甲球隊全軍覆沒。而本場比賽,裁判赫寧的醜陋表現,則完美的証實了歐足聯的計劃。是的,如果他們想讓巴塞奪冠,那即便是英超四強加在一起也打不過巴塞,原因很簡單,只是他們不願意看到英超的強勢。這個叫赫寧的裁判並不是沒有前科,08年歐洲盃他就因為在臨近終場前,判給了羅馬尼亞人一個12碼,差點導致意大利隊小組出局。賽後,赫寧被歐足聯處罰。而這樣的比賽,讓這樣一名有前科的裁判執法,很明顯,歐足聯的計劃昭然若揭。當政治可以凌駕足球,這是歐冠開始54年以來,賽場上發生的最為醜陋的一幕! 很多東西,事實就是事實,而真理則是無法被掩蓋的。多少年過去,信仰漂亮足球的巴塞儘管絲毫沒有打出漂亮足球,但仍然會被記載在歐冠晉級決賽的球隊榜上。而對於還相信「足球不是政治」、相信「真相必然不會被掩蓋」的球迷,事實上都已經清楚了,這場比賽的勝利者有且只有一個,那就是偉大的車路士。是的,他們今晚的表現無愧於偉大二字,相信這是每一位有良知的人,都會從內心中發出的聲音,無論你是巴塞球迷還是車路士擁躉。 ============ 今天只說這事,讓我冷靜...