Chemistry: Post your doubts here!

[abbas haider]

Something for Physics like this???

Yep ...
https://drive.google.com/drive/folders/0Bx_kNsO4S1YbTEZYb09ucmVLOEE

 

[Holmes]

Dude you are rocking!

By the way, where did you got these links?

 

[Holmes]

Dude you are rocking!

By the way, where did you got these links?

Yep ...
https://drive.google.com/drive/folders/0Bx_kNsO4S1YbTEZYb09ucmVLOEE

 

[abbas haider]

from here...
http://cieoandalevelnotes.blogspot.com/2015/04/physics-level-paper-5-p5-solved-papers.html

 

[Holmes]

from here...
http://cieoandalevelnotes.blogspot.com/2015/04/physics-level-paper-5-p5-solved-papers.html

Nice.

 

[Fathima Hd]

Please help me out with this!

 

[Fathima Hd]

A-1,2,3
B-1,2
C-2,3
D- 1 ONLY
PLEASE EXPLAIN THE ANSWER..ITS C

 

[Fathima Hd]

Please explain the answer

 

[Holmes]

A-1,2,3
B-1,2
C-2,3
D- 1 ONLY
PLEASE EXPLAIN THE ANSWER..ITS C

I hope I provided some useful explanations.
here you go:

 

[Holmes]

Can anyone help me out to Record values in additional columns?

 

[Hamnah Zahoor]

Please explain the answer

when you add KOH dissolved in ethanol it will remove bromine and a hydrogen from the compound and also form a double bond b/w the second and the third carbon showing cis-trans isomerism which forms a total of three isomers thus answer is B.

 

[Hamnah Zahoor]

Please help me out with this!

There is a ketone at the top and the bottom of the ring..C=O and there are four double bonds in the structure thus four pi bonds option D is correct.

 

[kity way]

Plz help! i dont get it

 

[Hamnah Zahoor]

Plz help! i dont get it

Q:3
2NaN3----->3N2
From one mole of sodium azide,
(3/2)*1=1.5 moles
place one mole of sodium from the first reaction equal to moles of sodium present in the second reaction
10Na=1 mole
thus,1/10=0.1
total 1.5+0.1=1.6

 

[Hamnah Zahoor]

Plz help! i dont get it

Q:39

statement 1: Consider an aldehyde ethanal being reacted with HCN it will increase a carbon in the compound thus increasing the length and also add a nitrile.
Statement 2: in order to remove the nitrile we add NaOH to hydrolyse it and remove the N and make acid. thus forming the required compound....
S:3 in order to form aldehyde we oxidise it gently(mild) then remove it by DISTILLATION which is not stated here thus 3 is wrong.

 

[kity way]

Q:39

statement 1: Consider an aldehyde ethanal being reacted with HCN it will increase a carbon in the compound thus increasing the length and also add a nitrile.
Statement 2: in order to remove the nitrile we add NaOH to hydrolyse it and remove the N and make acid. thus forming the required compound....
S:3 in order to form aldehyde we oxidise it gently(mild) then remove it by DISTILLATION which is not stated here thus 3 is wrong.

thank u soo much!!!

 

[kity way]

can someone help me with these?? thank u soo much!

 

[Hamnah Zahoor]

can someone help me with these?? thank u soo much!

Q:2 2017/13/june

X + H2O------>Al(OH)3 + hydrocarbon gas(HC)..unknown
HC(g) + O2------>H2O + CO2

cancel out the hydrocarbon and water molecules from both side of the equations to make it an overall equation
considering option D.

Al4C3 + 9O2+ 12H+ ------>4Al(OH)3 + 3CO2
mol of CO2=108/24000=4.5*10-3
3:1.......mol of Al4C3=1.5*10-3
Mr=144
option D is correct.

 

[Holmes]

Can anyone give me notes of
DNA +
AMINO ACIDS.
Thanks.

 

[Holmes]

Can anyone give me notes of
DNA +
AMINO ACIDS.
Thanks.

It seems as if every one have left this thread.