Chemistry: Post your doubts here!

[nehaoscar]

Why is it the same??

 

[shazmina]

View attachment 54717 how do we read the benzene rings? why is C chiral and not D?

When an OH group is directly bonded to a benzene ring it is knows as a Phenol ( you will learn this is in A2 chemistry in detail )
Therefore Option D has the Central carbon attached to two Phenols ( same group ) and thats why compound D isnt Chiral ...
Where as Compound C is attached to a phenol as well as a Benzene ring which are both different, along with Methyl and a Hydroxyl group .. Hope you understood

 

[nehaoscar]

Why C?? And Why not B??

 

[shazmina]

View attachment 54730
Why D?

Volume is inversely proportional to Pressure and Directly proportional to 1/P.. When Volume increases the pressure decreases as there will be less collision between the particles as well as with the walls of the container & Vice versa

 

[nehaoscar]

Fe(OH)2 has H-bonding then why is it insoluble??

 

[nehaoscar]

How to do this one??

 

[nehaoscar]

Why not D?? is sulfate soluble?? How??

 

[nehaoscar]

Why not C?

 

[shazmina]

View attachment 54733
Why C?? And Why not B??

K+ ion has lost 1 electron and now it contains only 18 electrons .. with 19 protons
S3- Ion has gained 3 electrons and now it contains 19 electrons along with 16 protons
Since K+ ion contains more protons ie higher +ve charge than S3- ion it will attract its electron more strongly than S3- ion
Coming to S3- ion, it has gained 3 electrons and now there will be greater repulsion between the gained electrons while keeping the same proton number and hence less attraction ... this is why S3- ion is larger than k+ ion

 

[nehaoscar]

How 6?? What happens when you react it with H2SO4??

 

[nehaoscar]

How is 2 correct? Why are they both metals?
And why is 3 wrong? They both form +2 so can they not be in the same group?

 

[nehaoscar]

Why is 2 correct?

 

[shazmina]

View attachment 54738
Why not C?

When Hydrocarbons are burnt CO2 and H2O will be given out & so we are not sure which Hydrocarbon was burnt. ( 1st statement )
Alcohols and Carboxylic acid react with PCl5 and liberate White fumes of HCl so again we are not sure which compound is it ( 2nd Statement )
Only Aldehydes and ketones react with 2,4 DinitrophenylHrdrazine, and hence we can be sure that this compound X wasnt an Aldehydes or a ketones

 

[nehaoscar]

I know why only 2 and 3 are correct but i want to know where will the Ca join on?
Like Na joins the COO- , where will Ca join since it requires -2 charge to join??

 

[nehaoscar]

When Hydrocarbons are burnt CO2 and H2O will be given out & so we are not sure which Hydrocarbon was burnt. ( 1st statement )
Alcohols and Carboxylic acid react with PCl5 and liberate White fumes of HCl so again we are not sure which compound is it ( 2nd Statement )
Only Aldehydes and ketones react with 2,4 DinitrophenylHrdrazine, and hence we can be sure that this compound X wasnt an Aldehydes or a ketones

Oh carboxillic acids also react with PCl5 Pcl2 SoCl2 etc..?

 

[BhaiArshad]

Explain?

 

[BhaiArshad]

Help?

 

[nehaoscar]

Explain?

If it's A
Then Kp = P.H20 x P.CO / P.H2 x P.CO2
You know the P.H2 and P.CO is 10000Pa each
And Kp is 0.288
So
P.H20 x P.CO = 10000 x 10000 x 0.288
Now the molar fraction for CO and H2O is the same so the Partial pressure will be same
So square root 10000 x 10000 x 0.288
which gives A

 

[shazmina]

Oh carboxillic acids also react with PCl5 Pcl2 SoCl2 etc..?

yes

 

[shazmina]

http://s21.postimg.org/vl3ml18xy/new_one.jpg
qwertypoiu The Sarcastic Retard can you please help me with this question ...
As far as i know, secondary alcohols when oxidised to ketones donot respond to mild oxidising agents, so i thought it might be a secondary alcohol, but is it wrong? can you pls clarify, the ans is D