Multiple Choice (2 Viewers)

[xmichaelpham]

1. B
2. D
3. A
4. C
5. B
6. C
7. D
8. D
9. B
10. B
11. B
12. D
13. D
14. A
15. C
16. A
17. C
18. C
19. A
20. A

Q12 is definitely D, the prefixes are order in alphabetical order but the numbers are where most electronegative is given lowest number.

ya this is what I think its all right

 

[Kimyia]

I thought the multiple choice was ok, but I can't remember what I put down so in saying that, I could have got them all wrong haha

 

[Zeroes]

I had 5 Bs in a row somewhere :| wooooooops

 

[kdizzler]

Your right, most electronegative goes first if both sides are equal lowest first number, and sum of numbers

 

[deswa]

1. B
2. D
3. A
4. C
5. B
6. C
7. D
8. D
9. B
10. B
11. B
12. D
13. D
14. A
15. C
16. A
17. C
18. C
19. A
20. A

Q12 is definitely D, the prefixes are order in alphabetical order but the numbers are where most electronegative is given lowest number.

Yep got all this except I put A for 13 though I had no clue so I'm probs wrong. I'm pretty sure IUPAC changed naming laws in 2005 so electronegativity no longer applies but I put D anyway. Wouldn't be surprised to see question removed imo

 

[Chulbul Pandey]

Fuck yes. Pretty sure I got 100% in multiple choice (went over w/ teacher after exam)
Here are answers I got in order.
B
D
A
C
B
C
C
D
B
B
B
D
D
A
C
A
C
C
A
A

Can we get a consensus on what was the correct 100% answers? Fairly sure the above is right.

Mine's pretty similar, except for:
7-D --> isn't bromothymol blue green in between 6 and 7.6??
16-B --> Wasn't the undotted line H2, cos they're are more mols of H2 in the eqn?? So doesn't that make it CO that is added?
17-A --> Had no idea how to do it. Guessed it, knew I'd get it wrong- I suck at guessing haha

 

[someth1ng]

Yep got all this except I put A for 13 though I had no clue so I'm probs wrong. I'm pretty sure IUPAC changed naming laws in 2005 so electronegativity no longer applies but I put D anyway. Wouldn't be surprised to see question removed imo

Yeah, but either way, the most correct is D. The names are in alphabetical order and numbers can be technically correct - at least you'd understand it.

 

[maths lover]

1. B
2. D
3. A
4. C
5. B
6. C
7. D
8. D
9. B
10. B
11. B
12. D
13. D
14. A
15. C
16. A
17. C
18. C
19. A
20. A

Q12 is definitely D, the prefixes are order in alphabetical order but the numbers are where most electronegative is given lowest number.

i got the exact same but im pretty sure that 13 is b. cr had a charge of +6 and went to +3 therefore is an oxidizing agent?, well atleast the naswer is between b and d.

 

[traiwit]

i got the exact same but im pretty sure that 13 is b. cr had a charge of +6 and went to +3 therefore is an oxidizing agent?, well atleast the naswer is between b and d.

That is a product after reduced

 

[someth1ng]

i got the exact same but im pretty sure that 13 is b. cr had a charge of +6 and went to +3 therefore is an oxidizing agent?, well atleast the naswer is between b and d.

Nah, it's D. Oxidising agent must be a reactant.

 

[maths lover]

Nah, it's D. Oxidising agent must be a reactant.

i dont think so, it can be the element itself as well, in fact i dont think its correct in saying the compound is being reduced as it is strictly the chromium ion that is being reduced.

 

[someth1ng]

i dont think so, it can be the element itself as well, in fact i dont think its correct in saying the compound is being reduced as it is strictly the chromium ion that is being reduced.

It asked for the oxidising agent in the reaction. I don't think it's possible to have an oxidising agent of a reaction as a product.

Anyway, it was originally Cr6+ and became Cr3+

.'. It gained electron and hence, was REDUCED.

.'. It is the oxidising agent.

 

[maths lover]

It asked for the oxidising agent in the reaction. I don't think it's possible to have an oxidising agent of a reaction as a product.

yeah probably, 19/20 is good enough.

 

[Sindivyn]

Aside from Q12, anyone want to explain to me why my answers are wrong? (Posted on the front page, seem to disagree with most answers on a few q's)

 

[someth1ng]

My Answers:
1B
2D
3A
4C
5B
6C
7D
8D
9B
10B
11C
12B
13D
14A
15C
16A
17C
18C
19A
20B

Q11. highest pH
Q20. A

PbCl2-->.595g
n=m/M=0.0021395mol

Work from there

 

[Sindivyn]

Q11. highest pH
Q20. A

PbCl2-->.595g
n=m/M=0.0021395mol

Work from there

Thanks
11 - misread
20 - Took it as PbCl instead of PbCl2.
Ah well, only 2 mistakes (or 3 depending on Q 12)

 

[Ant2511]

Fuck yes. Pretty sure I got 100% in multiple choice (went over w/ teacher after exam)
Here are answers I got in order.
B
D
A
C
B
C
C
D
B
B
B
D
D
A
C
A
C
C
A
A

Can we get a consensus on what was the correct 100% answers? Fairly sure the above is right.

Hey bro I got A for question 11 :/

 

[billy d]

why is 11 B

 

[habitres]

why is 11 B

Due to the fact that citric acid is triprotic, thus while being a weak acid similar to acetic acid, will donate 3* the H+ ion's and hence have a lower pH than acetic acid.

 

[Rawf]

Far out, by the looks of it i only got 18/20 for MC
I totally misread the question about the equip needed to make a primary standard solution and put the ans with 'pipette, burette and conical flask' and misunderstood the degree of ionisation when adding H2O to CH3COOH <_< I put it would decrease - i thought like.. with the water present it couldn't completely ionise in water and if you add more it wouldn't do anything so then the degree (% of ionisation) decreases lol fail.
Overall, I thought the MC was a bit tricky this time, the calculations and all were quite easy in it though.