Chemistry: Post your doubts here!

[Bilal.khan]

how is the answer c...
plz help

 

[Bilal.khan]

the marking scheme says answer is c but how r there 3 geometric isomers???

 

[shazmina]

View attachment 54634 how is the answer c...
plz help

The solubility of Group 2 hydroxides increases down the group .. so we can say that Barium hydroxide will be more soluble than calcium hydroxide ... hence when these two solutions are mixed together .. it will be the Calcium hydroxide that will be responsible for the white precipitate due to its less solubility compared to barium hydroxide .. and the filtrate will be containing Barium hydroxide .. And so when CO2 gas is bubbled to this filtrate .. it will react with Barium hydroxide forming Barium carbonate ...

Hope it helps !!!!!!

 

[Metanoia]

http://maxpapers.com/wp-content/uploads/2012/11/9701_s13_qp_12.pdf
somone help me out with question 21 guys

There are two C=C bonds.

When reacted with H2, it can take in 2 H2 molecules.
When reacted with Br2 it can also take in 2 Br2 molecules.

 

[Metanoia]

View attachment 54635 the marking scheme says answer is c but how r there 3 geometric isomers???

How many do you have?

 

[kesha27]

if the Ans is D...

Yeah its D thanks

 

[nehaoscar]

Please can someone clarify this doubt?

 

[nehaoscar]

View attachment 54635 the marking scheme says answer is c but how r there 3 geometric isomers???

There are 2 double bonds so you can have these combinations:
Cis at the first double bond and Cis at the second
So keep on changing and following the same pattern you can have:
C=cis and T= trans
CC
TT
CT / TC
Since the hex-2,4-diene is optically same (shows the same formula when read backwards and forwards), the CT and TC will count as one (it will just be a mirror image of each other)

 

[Metanoia]

View attachment 54646
Please can someone clarify this doubt?

There will be two oxygen atoms attached to form 2 ketone groups, one for each side.

 

[nehaoscar]

There will be two oxygen atoms attached to form 2 ketone groups, one for each side.

So the ring would open up?

 

[Xaptor16]

can someone please explain number 4? answer is A.

 

[Metanoia]

So the ring would open up?

Thats right.

 

[princess Anu]

why is statement 2 wrong in both the Questions?

 

[princess Anu]

how is statement 1 right?

 

[Metanoia]

View attachment 54648

can someone please explain number 4? answer is A.

 

[alevelpleasebegood]

I saw this question in a reference boo.
Which species is deflected the least in an electric field?
A. 24Mg2+ B. 27Al3+ C. 16O2- D. 31P3-?
Why is the answer A, not D? A-D has the same number of electron, but D has the largest number of proton. Proton is deflected the least in an electric field isn't it?

 

[The Sarcastic Retard]

I saw this question in a reference boo.
Which species is deflected the least in an electric field?
A. 24Mg2+ B. 27Al3+ C. 16O2- D. 31P3-?
Why is the answer A, not D? A-D has the same number of electron, but D has the largest number of proton. Proton is deflected the least in an electric field isn't it?

It has highest m-e ratio..

 

[alevelpleasebegood]

It has highest m-e ratio..

so m/e ratio not only affects the deflection in magnetic field, but also electric field?

 

[The Sarcastic Retard]

so m/e ratio not only affects the deflection in magnetic field, but also electric field?

thats the only reason that clicked my brain..

 

[Arsha A]

Could someone please answer 2011 May/June Paper 12 Question 35. The mark scheme says the answer is A but the same question is in 2008 May/June(Question 36) and the answer there is C.

Thanks.