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Friday, July 31, 2009 @ 10:31 PM
There's chemistry. HELLO EVERYBODY. Somethings so revise. Hah. ELEMENTS Definition: An element is a pure substance (made up of only one substance, without mixing with other substances) that cannot be broken down into simpler substances by chemical reaction, because it is the simplest form of matter. Hydrogen - H Helium - He Lithium - Li Beryllium - Be Boron - B Carbon - C Nitrogen - N Oxygen - O Fluorine - F Neon - Ne Sodium - Na Magnesium - Mg Aluminum - Al Silicon - Si Phosphorous - P Sulfur - S Chlorine - Cl Argon - Ar Potassium - K Calcium - Ca Iron - Fe Cobalt - Co Nickel - Ni Copper - Cu Zinc - Zn Bromine - Br Silver - Ag Iodine - I Gold - Au Mercury - Hg Lead - Pb Elements can be classified as METALS of NON-METALS. Metals: 1) Good conductors of heat. 2) Good electrical conductors. 3) Ductile - Can drawn into thin wires 4) Malleable - Can be beaten into sheets without breaking. Non-metals: 1) Poor eletrical conductors. 2) Brittle Diamonds and graphite are forms of carbon. Compounds: Made up of two or more elements chemically combined together. These are a few examples of compounds. Copper + Zinc = Brass Copper + Tin = Bronze Hydrogen + Oxygen = Water Nitrogen + Oxygen = Nitrogen Oxide Sodium + Chlorine = Sodium Chloride (Common Salt) Carbon + Hydrogen + Oxygen = Sugar Silicon + Oxygen = Sand Carbon + Hydrogen + Alcohol (Oxygen + Hydrogen with H6) = Ethanol Carbon + Hydrogen = Methane A compound may be broken down into simpler substances by chemical methods. Heat or electricity is usually required. Seperation techniques notes coming up tomorrow, if anyone wants it. Atoms Definition: Smallest most indivisible part of an element. Atoms are made up of: -Protons (forms the nucleus) -Neutrons(forms the nucleus) -Electrons (aroud the nucleus) Protons: Its relative mass is 1. Its relative electric charge is +1. Neutrons: Its relative mass is 1. Its relative electric charge is 0. Electrons: Its relative mass is approx. 0.0005 or 1/1836. Its relative electric charge is -1. The nucleus has a positive charge because of its protons. An atom is electrically neutral, therefore, the number of electrons = the nummber of protons. The nucleus has a positive charge cos' of its protons. The elctrons are negatively charged. Therefore, they are attracted to the positive nucleus. Because, (+)+(-)= attract! Opposites attract. THE NUCLIDE NOTATION OF NEUTRAL ATOM This is pretty important. Okay, I can't really put the symbols here so you can imagine it with my description. First, write the ELEMENT SYMBOL on the right hand side. Then, on the left side of the ELEMENT SYMBOL, for the top left corner, write the MASS NUMBER of the element. Then, on the bottom left corner, write the ATOMIC NUMBER of the element. That's the thingy I've been talking about. MASS NUMBER: The number of NEUTRONS+ the number of PROTONS. ATOMIC NUMBER: The number of PROTONS. ELEMENT SYMBOL: The element symbol. (example: Cl, B, F) ISOTOPES Isotopes are atoms of the same element with the same number of protons, yet with the different numbers of neutrons. (e.g. hydrogen) (Paiseh. I'm pretty confused about isotopes myself. But maybe you understand? If you do, please explain thx. But I'm 99% sure the information here is correct.) Why? Nucleon number is the sum of protons and neutrons. Therefore, different number of neutrons will give a different nucleon number. Tuesday, July 21, 2009 @ 7:49 PM
bwahaha. hel  loooo 111 !hahaha. it's been damn long since i came here blog. but since i've got nothing to do.. so. CRYSTAL has something against me coming here. i wonder why. aiya. but i won't say anything cause i' m nice! soo nice! there's nothing important to read in this post cause i'm really just crapping cause i have nothing else to do. AHG, I SOUND LIKE I HAVE NO LIFE. ahhh.. COMPETITION IN 2 DAYS! SIA PRESENTATION IN 2 DAYS! i really hate thursdays!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!! ahh, annoying . WISH ME LUCK. YO~~~~ 死草莓. you're the trotter-y pig. ( i have to type this. hahahahahahah. )  SINGAPURAAAAAAA! love, Ashley. Monday, July 20, 2009 @ 6:00 PM
Hey peeps. Science rep here {cassandra} Here are the topics for chem. in case you are a blur sotong like me :/ 1. Elements, compounds and mixtures 2. Seperation techniques 3. Atoms and molecules 4. Atomic structure and electronic configuration 5. Periodic table and group properties FYI: Section A ---10 marks, all MCQ Section B ---30 marks 50 minutes in total. Jiayous, and score well for chem okays? Au revoir! P/S Im reading Da Vinci code now, if you realise, so kindof in love with french >< Labels: Chemistry topics for BT Sunday, July 19, 2009 @ 4:42 PM
I dont care who posted the one in chinese,but its not me...although sometimes i tok like tt..u ppl dont mistaken me hor.. And btw,just wanna add on,u see ppl,me and yee xien somehow had some connection,and so we both did the same thing(u noe wat),which totally sucks.its not worth it...ur tears are not there for u to cry during CLC SIA presentation...so dont waste it like me.anw,U PPL DONT CRY AGAIN HOR!!!!tt time yee xien did it,i also cry for her...then i whole day damn pissed off..then even Cheryl said tt my face look like i wanna slap ppl..haha. SOOOO...get my point???!!haha...relax lar...aft CLC SIA,then can focus on Block test liao...hahah...so no need to worry..u will do CLC SIA every yr...dont tell me u be scared and hope tr dont call u rite?just face it.Impossible is nothing(ADIDAS ROCKS!!!!)random...HAHA..yeah..just jiayou.. YAY..i bought my W705 and CHOCS!!!haha...quite random...haha.. --STRAWBERRY PINK OINK OINK Friday, July 17, 2009 @ 7:38 PM
SIA 大家好。我知道这些话不应该是我说的。你不要读就管你了，不要那么 多嘴去批评别人。你们不需要知道我是谁。 同学们，我知道你们做这个SIA是很尽力的。那是很好的。 大家都会犯错的。老师是来让我们改过的，帮忙我们进步。 所以，不管李老师发了什么批评，我们要听，不要伤心。老师批评你是 为了帮忙你，不是要你伤心。 如果有个人骂你，你不应该想人家是因为讨厌你，或者要找你的麻 烦才这么做。我们应该想他们是要帮忙你的。人家关心你才会这么做的。 如果老师称赞你，就开心吧！这就表示你达到了老师对你的要求。但是 不要太骄傲哦。你能做的东西就是帮忙你华文比较微弱的同学们。 不要想，“我做了比他好多了，为什么老师骂我，没有骂他？”这是因为老师对你的希望比较高，所以，不应该为了这件事就伤心。 老师批评你的时候，就勇敢面对她的批评，不要微弱。 我知道大家都会成功的。希望这个会让你高兴一点儿，在你的脸上挂了个笑容。 加油大家！ PS 我不是老师。 Tuesday, July 14, 2009 @ 4:39 PM
Updates? HAHA. This is the 28th post of this blog! Is that good? Anyway, I am Clarissa [: Okay. I just received an email showing the audition time slot for Teachers' Day performance. Our class time slot is... 21st July(This coming Tuesday) erm. 3.40PM so yup. I think you will have to skip CCA UNLESS you are going for some competitions :) So ya. WE GOT TO PREPARE. At least like run through the song and stuff like that. JIAYOU for those presenting CLC SIA tomorrow! JIAYOUUUUUU! <3 yay. Okay. I think that's all ;) <3, Clarissa xD Monday, July 13, 2009 @ 9:53 PM
PSL Haha, I'm wondering who would be our class PSLs... :D Anyways, remember to bring your water bills for geog. People should update this blog more often. A blog run my one person has many more entries than a blog run by 33. Hahas oh and jiayou for CLC SIA. zaijian. Monday, July 6, 2009 @ 3:11 PM
Laugh Hello, crystal here. Erm, can I ask you all for a favour. When I present the chinese SIA... please don't laugh. Cos' laughter, to me, is much more contagious than H1N1. And if I laugh I can't talk! If I can't talk I fail! If I fail I... CRY! tyvm :) HAHA. BYEBYE. @ 11:37 AM
Hi ppl. its ur CLC rep here. LiLaoShi just called me to inform me some very important information. pls read carefully. Firstly, you will need t hand in ur CLC SIA on the day of presentation itself, which is next monday. no need to hand in seperately. just hand in after ur presentation. Secondly, when u r doing ur powerpoint slides, DO NOT WRITE IN ESSAY FORMAT. WRITE IN POINT FORM. and LiLaoShi said tt she will mark ur presentation according to point form, whether ur explanation is detailed enough, why u choose to use this theme, why pick those 5 compo...etc. Thirdly, the creativity of the CLC SIA takes mrks.pls do it well and not just get it down and thats it. spent some time to do it. Then, remember to ask LiLAoShi anythingtt u r not sure abt when sch starts...dont wait until the last minute and then ask her. she dont like tt. oh,btw, some ppl havent get ur CLC SIA yet right, dont worry, cause lilaoshi is sill marking ur SIAs, and she spent like damn lot fo time doing it cause we are damn lan. and anw, do make her effort pay off by doing a good job. Ppl like me, i also havent get my SIA yet..dont WORRY!!!!!!!!!!!!!!!!dont panic.. Ok.im dont passing my msg. GO TO LILAOSHI BLOG! she hav examples of the qian yan and hou ji, and u ppl are suppose to follow tt format, so better get it correct. if u ppl suddenly had memory lost and forget her URL, its www.solitary--walk.blogspot.com . -ur-everybody hated CLC REP....OINK! |