Chemistry: Post your doubts here!

[Hamnah Zahoor]

Thank you so much
Are you a graduate?

You are welcome.
No I am currently in As have my paper tomorrow.

 

[MShaheerUddin]

You are welcome.
No I am currently in As have my paper tomorrow.

OMG ._.
Srsly I can't believe it!

 

[MShaheerUddin]

Sorry for asking too many questions
Can you explain the above one
What is the reason behind slower reaction
Ans is D

 

[Hamnah Zahoor]

View attachment 63988
Sorry for asking too many questions
Can you explain the above one
What is the reason behind slower reaction
Ans is D

No it's ok.

At first the concentration decreased from 1.0 to 0.5 thus, slow reaction.
Calculate the number of moles for both reaction in second reaction more number of moles are produced thus more product will be formed
Option D.

 

[MShaheerUddin]

Why A is wrong?

 

[MShaheerUddin]

This?

 

[Hamnah Zahoor]

View attachment 63989
Why A is wrong?

Well I will advise you to focus on how a ester is formed.

 

[aloo Kha]

Oct-1-ene, CH3(CH2)5CH=CH2, can be thermally cracked. Which combination of compounds W, X, Y and Z can be obtained by thermally cracking oct-1-ene?

W CH2=CH2
X CH3CH=CH2
Y CH3CH2CH3
Z CH2=CHCH=CH2

A W, X, Y and Z
B W, X and Y only
C W, X and Z only
D W and X only

 

[Naveed Ul Ihsan]

in an experiment a sample of a pure gas is put into a gas syringe at a temperature of 300K and pressure of 16 kpa. the gas is compressed until the volume occupied by the gas is halved.
after the compression, the temperature of the gas in syringe is 375 and the pressure is 40 kpa.
is the gas is ideal

 

[sukasukinya]

Guys, teach me how to know the type of hybridization for each of the options. I really don't know how ( Helppp

 

[SohaibButt]

Carbon should be labelled.
And for carbon atoms to be in the same plane the angle between them should be 120 degrees.
View attachment 63981

Doesn't it form 120 as well?

 

[khadijaimran]

This is secondary alcohol but the point is, the sec alcohol must be like this ... "CH(OH)CH3" [Methyl group attached to the same carbon which is attached with OH group]

i get it thanks a lot!

 

[Hamnah Zahoor]

Guys, teach me how to know the type of hybridization for each of the options. I really don't know how ( HelpppView attachment 63994

Please First tell me is the answer to this question option C .
sp-triple bond
sp2 - double bond
sp3 - single bond

 

[MARZ132000]

Why is the answer B?

 

[Hamnah Zahoor]

Oct-1-ene, CH3(CH2)5CH=CH2, can be thermally cracked. Which combination of compounds W, X, Y and Z can be obtained by thermally cracking oct-1-ene?

W CH2=CH2
X CH3CH=CH2
Y CH3CH2CH3
Z CH2=CHCH=CH2

A W, X, Y and Z
B W, X and Y only
C W, X and Z only
D W and X only

You are not supposed to focus on how the thing is formed just the products should have carbon and hydrogen less than the original compound.Any combination can be produced thus the answer is A.
Examination report:
Question 24: The correct answer was A. The most commonly chosen incorrect answer was B. This suggests that many of the candidates’ decisions rested on whether or not CH2=CHCH=CH2 can be formed. This compound can be formed in the reaction CH3(CH2)5CH=CH2 → CH3(CH2)2CH3 + CH2=CHCH=CH2 hence the answer A.

 

[Hamnah Zahoor]

Doesn't it form 120 as well?View attachment 63995

 

[SohaibButt]

View attachment 64002

Thanks a lot

 

[khadijaimran]

Please First tell me is the answer to this question option C .
sp-triple bond
sp2 - double bond
sp3 - single bond

yes the ans is C

 

[Hamnah Zahoor]

yes the ans is C

Thanks

 

[SohaibButt]

I didn't get abt 5 membered ring....