i've shifted to blogspot. tabulas is ZZZ. new add: http://m1n1.blogspot.com/
cya!!

TO DO (in order): 1. Psychology Online Quiz 4 2. Biochem tut 3 & 4 3. Biochem Project - Glycolysis Pathway 4. DDCT quiz revision 5. DDCT debate preparation 6. Arts History Presentation 7. PIPC tut 2.2-2.3 7. DDCT project question 8. Biochem practical report TO GET: 1. Chest of drawers. white. for clothes. 2. Wardrobe. 2/3-doored. white. 3. Mirror. to stick on wall. 4. Bed frame. 5. Purple paint. 6. TV, 21". 7. New study desk, L-shaped. 8. Cushioned chair. I played mahjong on friday nite, paid $18 mahjong tuition fees lol. The time passed really really fast. I didn't feel very lethargic. Last night, went to J8 to catch a movie with CY. Wanted to watch INITIAL D, but the only available tix were the first-row seats. So, we watched A LOT LIKE LOVE instead. HAHA it's a NICE movie. funny. After ALOT LIKE LOVE ended, we SNEAKED into another theatre for INITIAL D. LOL. Just in time for their RACE! S$9.50 for two shows, well worth it man! There're ants running around on my desk. i have no idea which hole they came from. but there're no FOOD. NO FOOD OK ANTS ?!!! "getta shit outta here !!!" - STEVE's infamous quote.

BOO HOO HOO !!!!!!!!!!!!!!!! i'm super sad!!

Had my PIPC2 quiz at 5pm just now. Started at 508, ended at 548. KAOZZ so lil time. Actually is enough time one!! After i did my qn 2 then the tchr give the atomic mass, zzz! want to give give earlier la, lemme waste about 1min to redo!!! then after i finished the whole paper, i'm wondering, "eh, how come never make use of the Ka table provided ah?? and i nv do any dissociation of weak acids or bases??? WEIRD!" so i looked thru the qn, and .. =X !!!!! qn 1(b) i did wrongly!!!!!! realized HClO is a WEAK acid, but too late!!!!!!!!!!!!! CRY! didn't managed to finish tat qn in time, worth 5 or 6 marks loh!!! i know how to do one loh!! so wasted!!! veryvery very very very very very very very very SAD!!!!

the qn is : Calculate the pH of 0.5L of 0.0085M of HClO.

Initially, i dunno if HClO is Weak or strong acid lo. cuz the fucking HClO₄ is a strong acid, then i did it in the STRONG acid method. then i looked thru the K_a table (which is only applicable to WEAK acids), i found HClO!!!!!!!!!! but it's tooo late! gimme 20sec more and i can finish the qn, and earn 6 marks!! booooooo hoooooooooooooo!

the ans is:

HClO (aq) ↔ H⁺ (aq) + ClO^- (aq)

Initial:                      0.0085 M       0 M          0 M

Change:                      -X               +X            +X

Eqlm:                    (0.0085-X) M     X M          X M

Let X = [H⁺]

K_a = [H⁺][ClO^-] / [HClO], Given K_a = 3.0 X 10^-8

3.0 X 10^-8 = X² / (0.0085-X)

Assume X<5% Conc_initial, 0.0085 >> X,

thus, (0.0085-X) ≈ 0.0085M

X² = 0.0085 x 3.0 x 10^-8

X = 1.6 x 10^-5

Test assumption, X<5% [HClO]_initial

5% x 0.0085 = 4.2 x 10^-5

Assumption valid.

So, [H⁺] = 1.6 X 10^-5

pH = - log [H⁺] = - log (1.6 x 10^-5)

     = 4.80 !!!!!!!!!!!!!!!!!!!!!