Chemistry: Post your doubts here!

[Metanoia]

I dont get it.

Perhaps you can explain why you think the equilibrium on the left cell would change if sulfates was added, using any equilibrium equations you think is relevant.

 

[leenz98]

Perhaps you can explain why you think the equilibrium on the left cell would change if sulfates was added, using any equilibrium equations you think is relevant.

Which question are you referring to?

 

[Metanoia]

Which question are you referring to?

I'm referring to the reply by The Sarcastic Retard.

For your queries, you can click on the link on my signature "YouTube Videos for solutions to 9701 MCQ"

 

[leenz98]

I'm referring to the reply by The Sarcastic Retard.

For your queries, you can click on the link on my signature "YouTube Videos for solutions to 9701 MCQ"

I cant open this link.

 

[Metanoia]

I cant open this link.

Click on the heading of the video, it would direct you to youtube and you can look at the other videos.

 

[nehaoscar]

View attachment 58773
Part (ii)

Try using these two equations
so overall equation is:
Cr2O72- + 14H+ + 6Cr2+ ----> 8Cr3+ 7H2O
Ecell = 1.33 + 0.41
= 1.74V

 

[nehaoscar]

hmm..this question was addressed here.

https://www.xtremepapers.com/commun...st-your-doubts-here.9859/page-733#post-942233

order with respect to [CH3CHO] is 1
order with respect to [CH3OH] is 1

You would need answers to part a and b to find order with respect with H+, compare any two experiments and also sub in orders with respect to [CH3CHO] and [CH3OH].

e.g
Experiment 1 and 4

View attachment 58772

Thank you so much!

 

[Salonee B]

The numerical value for Ksp is 2.00 x 10–11. Calculate [Mg2+(aq)] in a saturated
solution of Mg(OH)2. Please help, I dont understand the mark scheme

 

[Metanoia]

The numerical value for Ksp is 2.00 x 10–11. Calculate [Mg2+(aq)] in a saturated
solution of Mg(OH)2. Please help, I dont understand the mark scheme

I'm assuming that your Ksp refers to the Ksp of Mg(OH)2.

 

[Salonee B]

I'm assuming that your Ksp refers to the Ksp of Mg(OH)2.

View attachment 58790

thank you very much!! And I will see to it that the stated details are included

 

[shahzaib9291]

can somebody guide me any good acdmy for A2 karachi?

 

[nehaoscar]

How is the mechanism nucleophilic substitution?
The CH3-CH2 attaches to the NH removing HBr, and the CH2 has a positive delta... so wouldn't it be electrophilic...
Please explain why it's nucleophilic :/
Metanoia

 

[nehaoscar]

Winter 2014 - P43 - Q8-c
Part i I got the same as ms

Can someone please explain how R has 4 absorptions
And how P and Q have 5

I got S as 2 because of the CH3 and CHO groups
P = CH3 , CH2 , CHO , CH3-CO and which other groups??
Similarly which ones for Q and R??
Metanoia

 

[Youknowwhoo]

Someday I'm gonna raid this thread and learn the stuff i need from here,has anyone tried this?

 

[a_wiserME!!]

can someone explain why A should have two OH and four H2O?? TIA

 

[nehaoscar]

View attachment 58827

can someone explain why A should have two OH and four H2O?? TIA

You should learn these reactions
They're in ligand exchange in transition elements
- example given in book is with Cu while here it is Ni but the overall reactions will be the same

 

[Dashing Cancerian]

View attachment 58827

can someone explain why A should have two OH and four H2O?? TIA

Because when dilute ammonia aqueous is used dropwise the NH3 not being a stronger base than the OH- cant take part in the reaction. As dilute ammonia aqueous means.
NH3 + 2 H2O -----> NH4+ + 2 OH-

The OH being the stronger one when dil NH3 is used in little amount reacts with Ni to displace Two aqua groups to form a complex [Ni(H2O)4(OH)2].
And as the Ni previously had a charge of +2 and OH is - and there are 2 OH thus the charge neutralises and the complex produced is neutral.

 

[a_wiserME!!]

Because when dilute ammonia aqueous is used dropwise the NH3 not being a stronger base than the OH- cant take part in the reaction. As dilute ammonia aqueous means.
NH3 + 2 H2O -----> NH4+ + 2 OH-

The OH being the stronger one when dil NH3 is used in little amount reacts with Ni to displace Two aqua groups to form a complex [Ni(H2O)4(OH)2].
And as the Ni previously had a charge of +2 and OH is - and there are 2 OH thus the charge neutralises and the complex produced is neutral.

You should learn these reactions
They're in ligand exchange in transition elements
- example given in book is with Cu while here it is Ni but the overall reactions will be the same

thnx guys yeah i kinda new the reaction but didnt exactly know the reason

 

[Dashing Cancerian]

thnx guys yeah i kinda new the reaction but didnt exactly know the reason

You got the reason now, right?

 

[a_wiserME!!]

You got the reason now, right?

yup I did.. thnx once again