inferiority complex thy suffer…

How should i start?
For those who hv no idea whats this entry all about, please refer to comments in " oh so takot".
Its been aaagesss  since i’ve left chemistry, i dont think i even remember takrifan asid anymore.
When a teacher asked me to write a chemistry essay,of course, u can expect i hv problems.

Problem no 1, theres no books, papers, notes or anything whatsoever about chemistry within my reach.sumer dh buang, the beloved notebook included.

Problem no2, nk essay bi ke bm?? if the former, ah…i ‘m not be able to help , am i? i mean, gambar rajah tenaga in bi aperh? energy profile diagram? ye ker?

If the latter,..urmm.. maybe i can lend some pointers .Note my choice of word, maybe.Last night, after all, i did find a chemistry book, my sister’s , actually( one of the perks having a twin sister , eh?)and did a bit of reading to refresh my memory, which took me a considerable 2 hours to finish bab" kadar tindakbalas" je.

oh well, cg roslynda, this one’s for you.

In Chemistry, there’s a few rule of thumb that i follow,

Rule no 1: The textbook is always right

Rule no 2: If in doubt, refer to rule no 1.

Rule no 3: Whatever the teacher writes, says and draw in class is the exact thing that u hv to write,  say,and draw in exam papers.So dont just stare at the teacher folks! write something.VERY HELPFUL.

Rule no 4: Do not read buku rujukan first thing.U”ll get a headache.What i did was, read the text book by heart, then read buku rujukan, if theres something in the buku rujukan that textbook dont have,, i either extract them, or highlight them so next time around , i just read the highlighted part . I dont read anywhere else bcoz its already in the textbooks.

Bottom line, ITS ALL THERE IN THE TEXTBOOKS.

Right, enough of introduction,.
Its early March so i estimated Fitfth formers should finished kadar tindakbalas by now.

In esSays, usually the question in this bab, will revolve around Teori Perlanggaran( Collision Theory)
Ada 4 factors right? namely, JUMLAH LUAS PERMUKAAN PER ISIPADU, SUHU, KEPEKATAN,TEKANAN, DAN MANGKIN.

oK. " Berdasarkan Teori Perlanggaran , terangkan kesan ………….  kepada kadar tindakbalas kimia…..

How to answer?

if JUMLAH LUAS PERMUKAAN PER ISiPADU( usually cerita pasal daging potong kecik2 , lebih cepat masak)

1.  Semakin kecil zarah, semakin besar JUMLAH LUAS PERMUKAAN PER ISIPADU zarah yg terdedah kepada tindakbalas or zarah yg bersaiz kecil mempunyai JUMLAH LUAS PERMIUKAAN PER ISIPADU yangb lebih besar BERBANDING zarah yang bersaiz besar

2.Semakin bertambah jumlah luas pemukaan, semakin bertambah peluang perlanggaran antara zarah

3. Bilangan pelanggaran bertambah, bilangan perlanggaran BERKESAN bertambah
4. Frekuensi perlanggaran BERKESAN bertambah
5. Kadar tindakbalas bertambah.

2 SUHU( temperature)

1. Semakin tinggi suhu, semakin tinggi kadar tindakbalas

1. Apabila suhu tinggi, tenaga kinetik zarah akan bertambah

2.Zarah mempunyai tenaga yang lebih tinggi akan bergerak dengan halaju yang tinggi.

3.Bilangan perlanggaran bertambah, bilangan perlanggaran BERKESAN  bertambah
4. Frekuensi perlanggaran BERKESAN bertambah
5. kadar tindakbalas bertambah

3. KEPEKATAN

1. Semakin bertambah kepekatan, semakin tinggi kadar tindakbalas.( generalising or ayat penyata am)

2.Semakin bertambah kepekatan, semakin banyak zarah dalam satu unit per isipadu larutan

3. Bilangan perlangaran antara zarah bertambah, bilangan pelanggaran BERKESAN bertambah
4. Frekuensi perlanggaran berkesan bertambah
5.Kadar tindakbalas bertambah

Tekanan also uses the same  answer as above. cuma in gas only.

MANGKIN 

1. Semakin banyak kuantiti mangkin, semakin tinggi kadar tindakbalas( generalising)

2.mangkin positif merendahkan tenaga pengaktifan satu tindakbalas untuk berlaku bagai menyediakan satu lintasan altenatif.

3.Lebih banyak zarah yang belanggar dapat melepasi tenaga pengaktifan baru yang lebih rendah

4. Bilangan perlanggaran BERKESAN bertambah
5. Frekuensi perlanggran BERKESAN bertambah
6.Kadar tindakbalas bertambah

Now, if u notice , theres kinda of pattern

ayat pertama adalh generalising
ayat kedua dan ketiga adalah reasoning
ayat 4, 5, 6( highlighted in blue) adalh fundamentals, which means hv to copy exact words if not , no marks.

What do people forget?

1. JUMLAH LUAS PERMUKAAN PER ISIPADU , people always forget the part highlighted in bold
2. In reasoning suhu, its compulsory to write, apabila suhu tinggi..
3. jumlah zarah per seunit isipadu larutan
4. the word "zarah", i’ve highlighted in red, its not wrong but its too general, must specify what zarah.
eg. molekul hidrogen…
     atom carbon…
     perlanggaran antara molekul-molekul… dengan molekul……
Get it?

Now, on to  bab Hidrokarbon pulak..

I’m going to talk about Sifat fizik ahli2 dlm Siri Homolog.
Which semuanya sama, right?
Semakin menuruni siri homolog, ….

1. TAKAT LEBUR DAN TAKAT DIDIH BETAMBAH
2. KEMERUAPAN BERKURANG
3. KETUMPATAN BETAMBAH
4. KEADAAN FIZIK BERUBAH DARI GAS—CECAIR—PEPEJAL
5. TIDAK MENGKONDUKSIKAAN ARUS ELEKTRIK, TIDAK LARUT DALAM AIR

For the first FOUR, reasoning adalah sama saja.

eg, " Mengapakah takat lebur bertambah/kemeruapan berkurang/ ketumpatan bertambah/keadaan fizik berubah. ,semakin menuruni siri homolog?"

Answer:

generalising: Semakin…… apabila  semakin apabila menuruni siri homolog
reasoning:  bilangan atom karbon per molekul alkana/alkena bertambah
                  saiz dan jisim molekul alkena/alkana betambah
                  daya tarikan antara molekul /Van der Walls bertambah kuat.
                  Lebih banyak tenaga haba yang diperlukan untuk memutuskan ikatan
concluding: maka takat lebur…/keadaan fizik…/kemeruapan…/  apabila semakin menurruni siri homolog.

note" for ketumpatan, reasoning sampai di " saiz dan jisim molekul alkana/alkena bertambah" sahaja.

for TIDAK MENGKONDUKSIKAN ARUS ELEKTRIK, its obvious isnt it?

mestilah 1. Alkana/Alkena adalah sebatian kovalen.
              2.terdiri drpd molekul-molekul kovalen ringkas.
               3.tiada ion-ion yang begerak bebas
               4. tidak boleh konduksi elektrik

to be continued….

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