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Chemistry: Post your doubts here!

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How to do??

CH3CH2OH + 2[O] ---> CH3CO2H + H2O
Mass of ethanol = 2.76g
Mr of ethanol = 12*2 + 5 + 16 + 1 = 46g/mol
Moles of ethanol = 2.76g / 46g/mol = 0.06mol
Moles of acid = 0.06mol
Mr of acid = 12*2 + 3 + 16*2 + 1 = 60g/mol
Theoretical mass of acid = 0.06mol * 60g/mol = 3.6g
Actual mass = 75% * 3.6g = 2.70g
 
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Compound X can be dehydrated --> it's an alcohol
Compound X cannot be oxidised ---> it's a tertiary alcohol.
Tertiary alcohol was dehydrated, so the resulting compound must have a double bond connected to a carbon atom that is connected to three other carbon atoms, which is only D.
Thank you so much :D i got it
 
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The question says that it is unreactive towards mild oxidising agents which mean it can not be a primary or a secondary alcohol as both can be oxidised .
It has to be a tertiary alcohol which is only possible in D :)
Thank you so much Brother.
 
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Q21: Can someone explain these to me? Metanoia
If the compound was an alkane and had no rings or double bonds, number of H atoms present = 2n+2 = 2(20)+2 = 42

Now, every time there're 2H less, you'll either have a double bond or a ring. The question states that there's one aldehyde (C=O) and 1 ring structure which has 1 C=C so this accounts for 6 missing Hydrogens, thereby leaving you with 8 missing Hydrogens.

8/2 = 4 Hydrogens in the aliphatic side chain.

However, total C=C are 5 because you have to include the C=C from the cyclohexene + cis formation hence A

I have attached the solution for Q11
 

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Al2O3 does not dissolve in water.

Na2O + H2O ----> 2Na(OH)
See, one mole of Na2O makes 2 moles of OH- ions.

P4O10 + 6H2O ---> 4H3PO4
See, one mole of P4O10 makes 4 moles of H+ ions.

SO3 + H2O ----> H2SO4
See, one mole of SO3 makes 2 moles of H+ ions.

For complete neutralization, same number of H+ and OH- ions must exist.
Therefore, answer is D.
 
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Q36 why is it C
Q why won't K2So4 cause excess growth? haven't we studied in Olevels that nitrogen phosphorus & potassium are the key elements in any fertiliser & are needed for growth :s
 

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Help please!!!!!
When an isomer Y of molecular formula C4H9Br undergoes hydrolysis in aq. alkali to form an alcohol C4H9OH, the rate of reaction is found to be unaffected by changes in concentration of the OH- ions present. Which is the most likely molecular structure of Y?

A CH3CH2CH2CH2Br
B CH3CH2CHBrCH3
C (CH3)2CHCH2Br
D (CH3)3CBr

The Ans is D......
 
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Help please!!!!!
When an isomer Y of molecular formula C4H9Br undergoes hydrolysis in aq. alkali to form an alcohol C4H9OH, the rate of reaction is found to be unaffected by changes in concentration of the OH- ions present. Which is the most likely molecular structure of Y?

A CH3CH2CH2CH2Br
B CH3CH2CHBrCH3
C (CH3)2CHCH2Br
D (CH3)3CBr

The Ans is D......
It is D because tertiary alkyl halides undergo reactions with SN-1 mechanism. This mechanism is independent of the concentration of reactants :)
 
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N forms 2 bond pairs and 1 lone pairs here right??
Then why 120degrees? wouldn't it be A?
 
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Propanone doesnt have H-bonding... It can not be mixed properly with propanal
The question says that the statements are all true
but just asks which ones are associated with H-bonding
So doesn't the mixing depend on H-bonding?
 
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