Multiple Choice (3 Viewers)

[crfrider]

anyone wanna attach a copy of the question sheet

 

[jamesfirst]

1. a
2. d
3. c
4. d
5. b
6. a
7. b
8. c
9. a
10. a (woops......)
11. d
12. c
13. c
14. d
15. b
16. b
17. c
18. a
19. b
20. d


.... who else got the same ?

 

[jamesfirst]

18 was A, I think.

There's a few others I got different in there, too...

18 was the exact same question from a past paper... wtf'


it was A

 

[jamesfirst]

20 was B mate

really ??

 

[jung1239]

So many different answers. Cant tell which ones are right.

 

[jamesfirst]

fk I failed M/C.........

 

[Wentworth]

15 was A, all weak acids/bases are fully ionized in reaction with a strong acid/base ,and they're both monoprotic... that's my reasoning anyway anyone do the same?

 

[khorne]

1. a
2. d
3. c
4. d
5. b
6. a
7. b
8. c
9. a
10. a
11. d
12. c
13. c
14. d
15. b
16. b
17. c
18. a
19. b
20. d


.... who else got the same ?

1. a
2. d
3. c
4. d
5. b
6. a
7. b
8. c
9. a
10. c (as H+ reacts with CO3, Ba reacts with SO4 and then only CL is left)
11. d
12. D most negative voltage to most possitive
13. c
14. c 1,1 chloro bromo=3,3 chloro bromo, 1,2 chloro bromo, 1,2 bromo chloro, 2,2 bromo chloro, 1,3 bromochloro = 3,1 bromochloro
15. A or C is possible, but I think it is A, simply because if it didn't dissociate fully, we couldn't work out the concentration.
16. b
17. D 108/2800 = number of moles
18. a
19. b ( i think I put this down, I didn't mark an answer on my sheet)
20. b 200g of each you get 466.66+733.33, goes nicely.

 

[silence--]

question 12 was D (DECREASING order - most reactive one first. the ones with negative reduction potential are stronger - see data sheet)

15 is A (i dont think it has anything to do with strength, its all V=n/c, 2010 hsc q7 had a similar question)

 

[Hayzazz]

Damn, I fucked up 12, I put C... Oh well, hopefully 19/20

 

[silence--]

also i agree with all of khorne's answers

 

[jamesfirst]

1. a
2. d
3. c
4. d
5. b
6. a
7. b
8. c
9. a
10. c (as H+ reacts with CO3, Ba reacts with SO4 and then only CL is left)
11. d
12. D most negative voltage to most possitive
13. c
14. c 1,1 chloro bromo=3,3 chloro bromo, 1,2 chloro bromo, 1,2 bromo chloro, 2,2 bromo chloro, 1,3 bromochloro = 3,1 bromochloro
15. A or C is possible, but I think it is A, simply because if it didn't dissociate fully, we couldn't work out the concentration.
16. b
17. D 108/2800 = number of moles
18. a
19. b ( i think I put this down, I didn't mark an answer on my sheet)
20. b 200g of each you get 466.66+733.33, goes nicely.

14. 15.

are u sure?/

 

[lolcakes52]

1/a 2/d 3/c 4/d 5/b 6/a 7/b 8/c 9/a 10/c 11/d 12/c 13/c 14/c 15/a 16/b 17/d(i think from memory) 18/a 19/b 20/b
15 is a due to the fact that the volume of NaOH is determined by the number of moles of acid which it reacts with, the number of moles of acid is determined by how many protons it can donate which in both cases is one. Therefore the amount of base required is the same.

 

[timting95]

I'm just curious, for question 12 it says 'electrochemical activity' does that mean that it's from positive to negative, negative to positive, or actually the largest MAGNITUDE to the lowest... i.e. B

 

[jamesfirst]

Shouldn't 14 be D and 15 be B ????


I even drew all the isomers and got 6 isomers.

 

[khorne]

14. 15.

are u sure?/

Yes, check it. I posted working

I'm just curious, for question 12 it says 'electrochemical activity' does that mean that it's from positive to negative, negative to positive, or actually the largest MAGNITUDE to the lowest... i.e. B

It doesn't matter. Electrochemical activity is the ability to engage in redox. The lower down, the less spontaneous

 

[CalumGemmell]

Shouldn't 14 be D and 15 be B ????


I even drew all the isomers and got 6 isomers.

No, there's 5. I'm not sure about 15, I put B as well. Could someone explain this?

 

[Nympha]

Shouldn't 14 be D and 15 be B ????


I even drew all the isomers and got 6 isomers.

You probably doubled counted one, as it can be rotated around.

 

[khorne]

Shouldn't 14 be D and 15 be B ????


I even drew all the isomers and got 6 isomers.

Dude...m8...cool your jets

You have the following:

Cl and Br on the same C at the end and at the start is the same, so thats one. Then on the middle, that makes total of 2. You have Cl on end, br on other end which is another 1 (doesn't matter which side) so thats 3. Then you have Br in middle, cl on one end and Br on one end, cl in middle, that makes 2 more, so 5. It's 5. The rest are repetitions.

15 is not B because weak acids ionise fully in titrations with strong ones.

 

[Nympha]

No, there's 5. I'm not sure about 15, I put B as well. Could someone explain this?

The answer would be A or C. A assumes degree of ionisation is irrelevant and that the weak acid will fully ionise. C assumes that a weak acid may not fully ionise, hence less H+ and hence less base is required to neutralize the H+.