Multiple Choice (3 Viewers)

[lolcakes52]

Fixed.

Nope, 9 isn't d it is a. It has nothing to do with the coordinate covalent bond. ozone is just like water except the hydrogens are replaced with oxygens, the molecule is bent but the electronegativity is the same so it isnt as polar as water but it is still polar.

 

[Bobbo1]

anyone got a correct set of solutions??

 

[rawrence]

I chose 15, b. I don't remember where I read it, perhaps from independent paper, but I swear I thought a stronger acid requires less base to neutralise...

 

[lolcakes52]

anyone got a correct set of solutions??

I am confident in my answers, there are no solutions as of yet though.
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 18/a 19/b 20/b

 

[Official]

15 is A

weak or strong does not make a difference

 

[Official]

I am confident in my answers, there are no solutions as of yet though.
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 18/a 19/b 20/b

12 is D, it asks for decreasing order of activity

 

[muzeikchun852]

15 is A

weak or strong does not make a difference

really ?

 

[silence--]

^yes

if you apply V=n/c with arbitrary numbers you can confirm

 

[Official]

really ?

yep, just think about that titration q in short answer, they asked citric acid which is a weak acid

by any other logic, other than 15 being A, equimolar citric and naoh should not have been added

 

[lolcakes52]

But silver is incredibly unreactive, more so than nickel. The less positive a metals reduction potential is the more reactive it is.

 

[Official]

But silver is incredibly unreactive, more so than nickel. The less positive a metals reduction potential is the more reactive it is.

yes, hence Cd > Ni > Ag > Pd

meaning that Cd is most reactive, and Pd is least reactive

decreasing = most to least

 

[Nympha]

But silver is incredibly unreactive, more so than nickel. The less positive a metals reduction potential is the more reactive it is.

Yeah that's true. So what are you arguing? By that logic it would be D as it goes from most reactive to least reactive...

 

[lolcakes52]

OMGOD, i thought those symbols where just arrows... dammit. worst mistake ever. i was reading left to right.

 

[crfrider]

anyone wanna upload a copy of question sheet

 

[d3st1nyLiang]

Agree with Khorne's answers.

 

[utanobeiiby]

ok heres mine with justifications for those hard ones... ><

1A
2D
3C
4D
5B
6A
7B
8C
9A Cause resonance and coordinate bond plays no role in solubility and since dissolving in water is not a reaction so O3 being reactive is irrelevant and O3 is bent so clearly polar no matter what resonance

10C just remember the rules

11B ok this one i was not sure between B or D but i chose B as the question said bromine WATER which exists as HBr and BrOH so possible products would be bromopropanol or bromopropane.. and i chose 2- bromo be cause the hydrogen tends to go on the carbon with the most hydrogen which is C1 so Br would be on c2 If the question says bromine LIQUID then it would be D. But since A and B are both possible B is just more likely to occur than A then that would make both A and B the right answer which we know is not possible... so that was why i was not sure of B or D ... If you guys have any thoughts please add...

12D ok the term electrochemical activity... is weird but i would interpret it as the reactivity of the metal? the potential to be oxidised? which mean we must inverset the sign and rank it??? .. anyways i dont think this question is legit...

13C logically thinking about C would show that it is true while everything else is just rubbish ... also for those who chose D .. addition of KCl into solution will release Cl- which favours forward reaction hence will be more blue... so C

14C Ok the thing as 3 carbons so no branching possible so no methyl... so the isomers would only differ in the position of the Br and Cl atom... the possible combinations are 1Br-1Cl, 2Br-2Cl, 1Br-2Cl, 1Cl-2Br, 1Br-3Cl so 5.. noting that any combinations of 3-3 2-3 would result in the same molecule.

15A weak acids ionise completely when excess base are added.. so behave identically to a strong acid and require same amount of base to neutralise

16B the Salt produced when a weak acid vs strong base is basic hence pH>7 while salts of strong acids vs strong bases are neutral

17D use 108/2800 for number of moles combusted then multiply by molar mas of C5H12O u get 3.9999... rounds to 3.40 D

18A ok so by NaX the base is capable of accepting 1 proton so mol of HCL used= Mole of NaX in 20Ml then x5 for Mole in 100ml= 0.0122 hence 0.0122 moles of Nax weighs 1 gram then molecular mass = 1/0.0122 = 82.0g

19B this is easy? just mass>mole>volume
20B easy.. mass to mole to mass..

 

[Nympha]

If anyone's interested I've uploaded the MC question sheet in the thread below. It's upside down and crap quality because I tried to scan it quickly - but you'll live. Enjoy.

 

[utanobeiiby]

Uploaded with ImageShack.us


probably wrong but still please have a look.

Ok firstly methylethane does not exist.. it is still propane you just named it wrong... because you are meant to count the longest carbon chain in this case is 3 no matter if you draw it straight or bent.. it is still a chain... so it is still propane so all of your methylethane things are just repetition of your other ones..

 

[danjw]

Anybody remember the questions well enough to put them up?

 

[jamesfirst]

18A ok so by NaX the base is capable of accepting 1 proton so mol of HCL used= Mole of NaX in 20Ml then x5 for Mole in 100ml= 0.0122 hence 0.0122 moles of Nax weighs 1 gram then molecular mass = 1/0.0122 = 82.0g

Did anyone realise that 18 was in the past HSC paper???


Like exact wording. Well, it was in the Success One book and I was surprised when I saw it..