Chemistry Predictions/Thoughts (4 Viewers)

[dubbatee]

But is that not assuming that 100% will react one way and that it could be either precipitate or a mixture

Yeah it is. But if we use the molar solubility correctly like the person who wrote the catalyst solution, then it says that we have 1.1 x 10^(-4) M Mg2+ in solution. Using that would agree with 1 ppt even further, that quantity is 10x smaller than the value im using

 

[C2H6O]

Is Q13 wrong should it be exothermic

It was c right (I CHANGED TO B CAUSE I MISREAD THE SIGN KILL ME)

 

[iane]

Catalyst is saying d

 

[lawfirm]

Yeah it is. But if we use the molar solubility correctly like the person who wrote the catalyst solution, then it says that we have 1.1 x 10^(-4) M Mg2+ in solution. Using that would agree with 1 ppt even further, that quantity is 10x smaller than the value im using

Except is that not saying there will be completion for either hydroxide or carbonate which may not happen

 

[iane]

Waiti can someone explain why 14 is b

 

[nowomansland]

Catalyst is saying d

oh their reasoning is correct tho it’s c might’ve been a typo

 

[lucas10champ]

was i the only one that thought that was a cooked paper?

yea it was pretty easy

 

[nowomansland]

Yeah it is. But if we use the molar solubility correctly like the person who wrote the catalyst solution, then it says that we have 1.1 x 10^(-4) M Mg2+ in solution. Using that would agree with 1 ppt even further, that quantity is 10x smaller than the value im using

so that does mean 1.1 x 10^-4 is the amount of Mg2+ that remains in the solution and 0.0059 is what precipitated out?

 

[lawfirm]

wait but with this ksp, is the Mg2+ not still going in and out of solution and can be in a situation where the same Mg is flicking between OH- and CO32-

 

[LittlePig107]

For the ppte q it was selective precipitation - only magnesium hydroxide will form

 

[nowomansland]

wait but with this ksp, is the Mg2+ not still going in and out of solution and can be in a situation where the same Mg is flicking between OH- and CO32-

the mg2+ would react w OH- first bc it’s Ksp is lower so it’s more insoluble

 

[LittlePig107]

where are the catalyst sols?

 

[BionicMango]

it wasn’t asking if the eq position changes tho it was if temp of system will change so i’m really confused

Yeah it’s a weird one, made me think as well and I’m definitely not 100% sure about this but basically the the keq only changes if the temperature changes, which would only change if someone added an EXTERNAL change in temperature. And if the concentrations of everything is still the same then the keq is still the same so the temperature has to be the same.

Think of it in terms of collision theory - sure more particles are bumping into each other, more of those are actually with the inert gas which it won’t react with, so in the end there is no net effect.
Remember PV=nRT? Because n increases, pressure increases, so it stays balanced WITHOUT a change in temperature. No change in temperature and no change in concentrations means no change in Keq

 

[iane]

How wi scaling look like

 

[BionicMango]

How wi scaling look like

Probs better than last two years

 

[LittlePig107]

For q19 I got C
And 20 I got b

Are those right?

19 was d, 20 was b

 

[LittlePig107]

Yeah it’s a weird one, made me think as well and I’m definitely not 100% sure about this but basically the the keq only changes if the temperature changes, which would only change if someone added an EXTERNAL change in temperature. And if the concentrations of everything is still the same then the keq is still the same so the temperature has to be the same.

Think of it in terms of collision theory - sure more particles are bumping into each other, more of those are actually with the inert gas which it won’t react with, so in the end there is no net effect.
Remember PV=nRT? Because n increases, pressure increases, so it stays balanced WITHOUT a change in temperature. No change in temperature and no change in concentrations means no change in Keq

What happens is that the partial pressure remains constant, and so pretty much nothing happens - really wierd 4 marker

 

[LittlePig107]

bro please can someone post the catalyst sols

 

[BionicMango]

For q19 I got C
And 20 I got b

Are those right?

I got D for 19. The solution is being diluted so pH goes towards 7. And it’s not a acid/conjugate pair so it’s not a buffer system.
For 20 I got B as well

 

[C_master]

19 was d, 20 was b

pretty sure 19 was confirmed c