ATAR Notes: Forum

Archived Discussion => 2010 => Mid-year exams => Exam Discussion => Victoria => Chemistry => Topic started by: Studyinghard on June 09, 2010, 02:38:09 pm

Title: FIRST MULTIPLE CHOICE
Post by: Studyinghard on June 09, 2010, 02:38:09 pm

ALL OPTIONS WERE WRONG. WTF. ?

Title: Re: FIRST MULTIPLE CHOICE
Post by: curious111 on June 09, 2010, 02:39:04 pm

Strong acid added to weak base wasn't it?

Title: Re: FIRST MULTIPLE CHOICE
Post by: 10weid on June 09, 2010, 02:39:09 pm

not at all,....
weak base started at pH of 10, equiv. point was at abt 4.5, indicating a strong acid had been added, and the pH ends up below 2, indicative of a strong acidd...

Title: Re: FIRST MULTIPLE CHOICE
Post by: crayolé on June 09, 2010, 02:40:17 pm

That was B right?

Title: Re: FIRST MULTIPLE CHOICE
Post by: Studyinghard on June 09, 2010, 02:40:47 pm

How can it be a weak base if pH is 10???

Title: Re: FIRST MULTIPLE CHOICE
Post by: 10weid on June 09, 2010, 02:41:38 pm

bcoz strong base is pH14, and nutral is pH7, thus, 10 is closer to 7 than 14, and it is a weak base - it ionises to a small extent in solution...
and no, it was option C i think..

Title: Re: FIRST MULTIPLE CHOICE
Post by: Studyinghard on June 09, 2010, 02:42:57 pm

I got option C but I just thought it was a bit ambiguous with weak base with a pH of 11. anywho no harm done. except now i think that you are right that 4 was 5/7

Title: Re: FIRST MULTIPLE CHOICE
Post by: tram on June 09, 2010, 03:06:28 pm

it was adding string acid to a weak base.....option c i think...