Chemistry: Post your doubts here!

[awesomaholic101]

Omg i seriously forgot this sis A2 topic
Thank you sooo much JazakAllah khairan

i didnt know this until today coz i am only doing AS now ... so thank YOU .... these stupid ppl asking unwanted questions
Wa iyyak

 

[Metanoia]

Sorry but i didnt get the Ionisation part :/

Actually, the most straightforward way to tackle this question is to refer to the list of IE and ionic radii in the data booklet as suggested by the question, and see which option fits the description.

 

[The Sarcastic Retard]

Actually, the most straightforward way to tackle this question is to refer to the list of IE and ionic radii in the data booklet as suggested by the question, and see which option fits the description.

This method is now in my nerves... Ty..

 

[nehaoscar]

The oxygen is in excess, methane for example won't burn in a 1:7 ratio with oxygen! So the oxygen is left and the volume decreases as more oxygen is used up.

Oh i see! i was only taking CO2 volume in consideration Thankyou!

 

[nehaoscar]

Help! it's 1 and 2 only
How would each react and what will it give in each case? And what would 3 give since it's wrong??

 

[nehaoscar]

Why A?
CH4 has the maximum bond energy...

 

[nehaoscar]

Why D?
Isn't it
Mg = 0.5mol O2
Al = 0.75mol O2
S = 1mol O2 (since SO2 is formed right as SO3 required a catalyst)??

 

[mahlom]

oh i think i realised ur mistake ... u are counting both Carbon atoms in two of the C=C double bond ... i don't think we should do that ...

Can you plz mark the places where it will be changed to ketone?

 

[nehaoscar]

Why C??

 

[nehaoscar]

Why C? Why is it bad if ammonia is given off?

 

[shazmina]

IE naturally increases across the period because the nuclear charge is higher, so Mg wil lhavve more IE than Na. It will also have more IE than Al, because Al has an electron in the outer p shell which has more energy and is also farther than the nucleus. (Mg outer shell => 3s2, Al outer shell => 3s2 3p1)

Thanks alot i got it

 

[shazmina]

Actually, the most straightforward way to tackle this question is to refer to the list of IE and ionic radii in the data booklet as suggested by the question, and see which option fits the description.

Thank you

 

[nehaoscar]

How will A give 3 alkenes? I can only find 2 ... :/

 

[The Sarcastic Retard]

View attachment 54846
Why A?
CH4 has the maximum bond energy...

HCl have very high difference of electronegetivity b/w them than other molecules... hence it has intermolecular force.... which diviates it from ideal gas the most.

 

[asadalam]

View attachment 54850
How will A give 3 alkenes? I can only find 2 ... :/

One will be But-1-ene,and the other will be But-2-ene which will show cis-trans isomerism at the double bond.

 

[princess Anu]

During Dehydration of an alkene, H2So4 acts as a catalyst or as a reactant?

 

[The Sarcastic Retard]

View attachment 54847
Why D?
Isn't it
Mg = 0.5mol O2
Al = 0.75mol O2
S = 1mol O2 (since SO2 is formed right as SO3 required a catalyst)??

6A*student credits.
This is oxidation reactions forming oxides
eg. 1 Mg + 0.5O2 -> 1MgO
1 Al + 0.75O2 -> 0.5Al2O3
1 S + 1O2 -> 1 SO2 because its in excess oxygen 1SO2 + 0.5 O2 -> 1SO3 so overall equation is 1S + 1.5O2 -> 1SO3

the oxidation ratio is 0.5:0.75: 1.5 = 2:3:6 = 1:1.5:3 so answer is D

 

[asadalam]

Actually, the most straightforward way to tackle this question is to refer to the list of IE and ionic radii in the data booklet as suggested by the question, and see which option fits the description.

Can some1 please explain this

 

[nehaoscar]

6A*student credits.
This is oxidation reactions forming oxides
eg. 1 Mg + 0.5O2 -> 1MgO
1 Al + 0.75O2 -> 0.5Al2O3
1 S + 1O2 -> 1 SO2 because its in excess oxygen 1SO2 + 0.5 O2 -> 1SO3 so overall equation is 1S + 1.5O2 -> 1SO3

the oxidation ratio is 0.5:0.75: 1.5 = 2:3:6 = 1:1.5:3 so answer is D

Dayum xD Some questions they want you to take in account the catalyst... others they dont :S

 

[awesomaholic101]

Can you plz mark the places where it will be changed to ketone?