Chemistry Predictions/Thoughts (3 Viewers)

Interdice

Well-Known Member
Joined
Jun 24, 2021
Messages
522
Gender
Male
HSC
2023
Also for Q16. The answer is the compound with the bigger ksp. Right?
 

ghreysantomy

New Member
Joined
Oct 16, 2023
Messages
14
Gender
Male
HSC
2023
Also for Q16. The answer is the compound with the bigger ksp. Right?
Q16 was (B)
=> AgI precipitates out first as it has a SMALLER Ksp and so less of it needs to be added into a given volume before it begins to precipitate, compared to AgCl, whose Ksp is larger. The solutions, by PEAK, were posted on this thread a few days ago.
 

Interdice

Well-Known Member
Joined
Jun 24, 2021
Messages
522
Gender
Male
HSC
2023
Q16 was (B)
=> AgI precipitates out first as it has a SMALLER Ksp and so less of it needs to be added into a given volume before it begins to precipitate, compared to AgCl, whose Ksp is larger. The solutions, by PEAK, were posted on this thread a few days ago.
Thanks
 

sneak11

New Member
Joined
Nov 19, 2021
Messages
10
Gender
Male
HSC
2023
if for the 9 mark spectroscopy question i had put carboxyl accidentally instead of carbonyl but put (ketone) in brackets, is there a possibility i might still get that mark?
 

Luukas.2

Well-Known Member
Joined
Sep 21, 2023
Messages
444
Gender
Male
HSC
2023
if for the 9 mark spectroscopy question i had put carboxyl accidentally instead of carbonyl but put (ketone) in brackets, is there a possibility i might still get that mark?
If you've drawn a ketone, written ketone, and spoken of carbonyl (correctly) in the justification that accompanies the table, I think there is a far argument to be made that you should be credited despite a minor mistake. However, if you've made the same mistake in the justification or if your answer (overall) comes across as reflecting uncertainty or as being mistaken, being penalised is the fair outcome.

Having said that, if the marking scheme treats the table and structures specifically and separately, then you could be out of luck.

Note, also, that giving two answers is generally discouraged. Suppose someone wrote carbonyl (aldehyde) and then drew a ketone, for example... the functional group is correct but the additional (and unrequested) compound class is incorrect. Should that be ignored? What if the answer said "aldehyde (carbonyl)," so that the second answer is the correct one?

In your case, would you credit the answer ketone alone, without the proper name of a functional group provided? I would argue against that being credited, but an earlier question incorrectly portrayed aldehydes and ketones as having different functional groups, so taking a hard line on functional groups vs. compound classes seems harsh.

So... is there a possibility of you getting the mark? Yes. Is there a possibility of you doing anything to influence the decision now? None at all. My advice is: move on.
 

Interdice

Well-Known Member
Joined
Jun 24, 2021
Messages
522
Gender
Male
HSC
2023
Do u get marks for half equations?

For example Q24, I wrote
HC2O4- + H+-> H2C2O4
 

Users Who Are Viewing This Thread (Users: 0, Guests: 3)

Top