Chemistry: Post your doubts here!

[Hiba shahid]

Hello , I wanted to ask if we can write alkyl groups such as methyl (CH3) in skeletal formula

 

[princess Anu]

PV = nRT
R and T are constant. So we can write:
PV = kn, where k is just a constant.
n = PV/k
Moles of gas in flask X = 2*1/k = 2/k
Moles of gas in flask Y = 1*2/k = 2/k
Total moles = 4/k
New volume together = 1+2=3
New pressure = kn/V = k * (4/k) / 3 = 4/3Pa

Can't we find moles like
vol given/24 .. i.e...(1/24 + 2/24)?

 

[nehaoscar]

But A and B will run out at some point

So even if they hadn't mentioned the product catalysing the reaction, the graph would still look the same as the reactants would eventually run out right.?

 

[nehaoscar]

Hello , I wanted to ask if we can write alkyl groups such as methyl (CH3) in skeletal formula

Yes
For example:

 

[nehaoscar]

What would each give as a result with C?

 

[nehaoscar]

Does LiAlH4 give nascent hydrogen?

 

[nehaoscar]

Why is D - the teritary one not affected by the OH concentration?

 

[nehaoscar]

Between what would forces 2 and 3 be?

 

[nehaoscar]

Doesn't K2Cr2O7 turn from orange to green ? (2) but only 1 is correct :?

 

[Mathemagical]

View attachment 54555
What would each give as a result with C?

SiO2 is acidic and will not react with hydrochloric acid.
Calcium carbonate will react with hydrochloric acid to form calcium chloride, carbon dioxide and water.

 

[Mathemagical]

View attachment 54556
Does LiAlH4 give nascent hydrogen?

LiAlH4 is commonly used as a reducing agent. In this case, it reduces the aldehyde into a primary alcohol.

 

[Mathemagical]

View attachment 54557
Why is D - the teritary one not affected by the OH concentration?

Since it is not affected by OH- ions, the reaction mechanism is Sn1. Only tertiary halogenoalkanes undergo Sn1 reactions.

 

[Mathemagical]

View attachment 54558
Between what would forces 2 and 3 be?

Permanent dipole would be C=O, and induced dipole would be C-N

 

[Mathemagical]

View attachment 54559
Doesn't K2Cr2O7 turn from orange to green ? (2) but only 1 is correct :?

The organic product is a carboxylic acid, which is not coloured.

 

[shazmina]

http://postimg.org/image/kv4auw8xd/full/
Can any1 please explain me why option 2 is not considered?

 

[nehaoscar]

SO2 + Ca(OH)2 ---> CaSO3 + H2O

Thats the main product formed initially
So is there a different final product?

 

[Mathemagical]

http://postimg.org/image/kv4auw8xd/full/
Can any1 please explain me why option 2 is not considered?

Option 2 is a salt, so it will be found in the flask. The question specifies on the distillate.

 

[qwertypoiu]

So even if they hadn't mentioned the product catalysing the reaction, the graph would still look the same as the reactants would eventually run out right.?

Then it would have been D

 

[qwertypoiu]

Can't we find moles like
vol given/24 .. i.e...(1/24 + 2/24)?

It may give you the correct final answer, however, technically that assumption is wrong, since 1 mole of gas occupies 24 litres only in room temperature and pressure

 

[nehaoscar]

Then it would have been D

Ah yes! And say if it was catalysed by a different catalyst... then it would be C right?