Chemistry: Post your doubts here!

[princess Anu]

Q36 why is it C
Q why won't K2So4 cause excess growth? haven't we studied in Olevels that nitrogen phosphorus & potassium are the key elements in any fertiliser & are needed for growth :s

 

[princess Anu]

why is option C wrong? I do get three alkenes with it

 

[shazmina]

Help please!!!!!
When an isomer Y of molecular formula C4H9Br undergoes hydrolysis in aq. alkali to form an alcohol C4H9OH, the rate of reaction is found to be unaffected by changes in concentration of the OH- ions present. Which is the most likely molecular structure of Y?

A CH3CH2CH2CH2Br
B CH3CH2CHBrCH3
C (CH3)2CHCH2Br
D (CH3)3CBr

The Ans is D......

 

[princess Anu]

Help please!!!!!
When an isomer Y of molecular formula C4H9Br undergoes hydrolysis in aq. alkali to form an alcohol C4H9OH, the rate of reaction is found to be unaffected by changes in concentration of the OH- ions present. Which is the most likely molecular structure of Y?

A CH3CH2CH2CH2Br
B CH3CH2CHBrCH3
C (CH3)2CHCH2Br
D (CH3)3CBr

The Ans is D......

It is D because tertiary alkyl halides undergo reactions with SN-1 mechanism. This mechanism is independent of the concentration of reactants

 

[nehaoscar]

N forms 2 bond pairs and 1 lone pairs here right??
Then why 120degrees? wouldn't it be A?

 

[psychiatrist]

View attachment 54751
N forms 2 bond pairs and 1 lone pairs here right??
Then why 120degrees? wouldn't it be A?

Total 3 valance pair.. so 120 degress or slightly lesser than 120

Can someone explain these to me? Metanoia qwertypoiu

Q9 C=C=O ; O have 2 LP and C have 1 LP

 

[nehaoscar]

How to do this one??

 

[psychiatrist]

View attachment 54756
Why is 3 wrong? If something can form H-bonds then it will mix right?

Propanone doesnt have H-bonding... It can not be mixed properly with propanal

 

[nehaoscar]

Total 3 valance pair.. so 120 degress or slightly lesser than 120

Q9 C=C=O ; O have 2 LP and C have 1 LP

How 3 valence pairs? Don't you only count the sigma bonds and not the pi bonds? and what about the 1 lone pair?

 

[nehaoscar]

Propanone doesnt have H-bonding... It can not be mixed properly with propanal

The question says that the statements are all true
but just asks which ones are associated with H-bonding
So doesn't the mixing depend on H-bonding?

 

[psychiatrist]

Can someone explain these to me? Metanoia qwertypoiu

2) 68-31 = 37

 

[psychiatrist]

The question says that the statements are all true
but just asks which ones are associated with H-bonding
So doesn't the mixing depend on H-bonding?

NO :/

 

[psychiatrist]

How 3 valence pairs? Don't you only count the sigma bonds and not the pi bonds? and what about the 1 lone pair?

2 BP and 1 LP = 3 valance par of electorns..

 

[nehaoscar]

2 BP and 1 LP = 3 valance par of electorns..

Oh haha thanks! idk my head was screwed up xD

 

[nehaoscar]

Why is it the same??

 

[asadalam]

Why is it the same??

I think its enthalpy change per mole H20 formed,as same moles formed and enthalpy of neutralisation is mostly 56-57 its C.

 

[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?

 

[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??

 

[asadalam]

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?

Transition elements.Cu and Mg can have +2 but they arent in same group