TrueTears question thread

[TrueTears]

Thanks for that chem-nerd

[TrueTears]

Just a question:

1. For this reaction of Ethene: Is it called an addition reaction or hydrolysis? Or are both acceptable? I think hydrolysis because it's specific.

[kurrymuncher]

3. I think you should name it hydrolysis, as that is the "specific" name of the reaction. Most alkenes will undergo addition reactions anyway, so it would be better if you label the actual name of the reaction.


remember that the type of reaction is addition, and the specific name of the reaction is hydrolysis.

[TrueTears]

3. I think you should name it hydrolysis, as that is the "specific" name of the reaction. Most alkenes will undergo addition reactions anyway, so it would be better if you label the actual name of the reaction.

Thanks

[TrueTears]

Questions:

1. (this one is quite trivial but nonetheless) After the cracking of a crude oil fraction, one of the products is found to be a gas at room temperature. The substance is also a hydrocarbon containing 85.71% carbon by mass. Name one product from the cracking process.

I worked out the empirical formula to be but I don't see how this relates to the question. Crude oil can crack into heaps of different smaller hydrocarbons, but I don't know the chemical formula of crude oil so how do I know what one product it cracks into?

2. The mass spectrum of contains a peak at 27, what would this peak be?

I think its , but can it also be ?

3. Say you got an amino acid, when it's placed in an acidic solution heinemann says this form is the most abundant , where Z is a side chain. However say you got this amino acid:

Does the in the side chain () also get turned into a or just the one that's on the first( ) carbon?

[Mao]

3. I think you should name it hydrolysis, as that is the "specific" name of the reaction. Most alkenes will undergo addition reactions anyway, so it would be better if you label the actual name of the reaction.


remember that the type of reaction is addition, and the specific name of the reaction is hydrolysis.

Small technicality:

There is a difference between 'hydrolysis' and 'hydration'

In when water reacts in an addition reaction with a double bond, it is a 'hydration' reaction.

A + H2O --> B

In terms of organic chemistry, hydrolysis usually involve splitting of a larger molecule when reacting with water

A + H2O --> B + C

(and same goes for dehydration [A --> B + H2O] and condensation [A + B --> C + H2O])
These are not the most technically correct definitions, as hydrolysis doesn't necessarily split molecules in inorganic, physical and electrochemistry, but it will do

[Mao]

1. gas at room temperature usually implies the number of carbons to be less than 4. So it can be any of these:

ethene
propene
butene
isobutene
cyclopropane
cyclobutane


2. I'd say yes to both (though 27 is a weird fragment to be getting...)

3. Yes, the -NH2 on the side group can act as a base

[TrueTears]

Thank you Mao!  8-)  :coolsmiley: life saver yet again

[methodsboy]

3. I think you should name it hydrolysis, as that is the "specific" name of the reaction. Most alkenes will undergo addition reactions anyway, so it would be better if you label the actual name of the reaction.


remember that the type of reaction is addition, and the specific name of the reaction is hydrolysis.

hydrolysis? when did we learn that?
i dnt remember her talking bout that.
EDIT: nvm, it's when a chloroalkane turns into a alkanol

[jaja]

n(CO(NH₂)₂) = 1/2 n(H₂NCH₂COOH)

thus, A

Why isnt it 1:2?

[TrueTears]

A few trivial questions.

1. A question says "Draw the structure of the two different monomers which make up this polymer." One of the monomer was . When I draw the structure do I need to show the lone pair on the nitrogen? Or can I just leave it out.

2. Using semi-structural formulas write the reaction to turn ethene into ethanol.

My answer was: This equation is from the heinemann.

However answer has


Which one is correct?

Thanks.

[lacoste]

2. Using semi-structural formulas write the reaction to turn ethene into ethanol.

My answer was: This equation is from the heinemann.

However answer has


Which one is correct?

Thanks.

Both is correct as H+ is showing that its in an acidic environment: (Phosphuric Acid), H+ indicates that its from an acid. Its fine writing H2O/H+ at the top of the arrow.

I would go your answer if in an exam as this shows more clarity in regards with H3PO4 as its triprotic, can easily donate protons

[TrueTears]

Ohhh cool, thanks for that lacoste!

[TrueTears]

In a recent lisa chem test I have done the process of converting to using as reactant was called an addition, but I said it was a hydrolysis, the answers only had addition. If this happened in the exam would I be wrong or right?

Thanks!

[/0]

3. I think you should name it hydrolysis, as that is the "specific" name of the reaction. Most alkenes will undergo addition reactions anyway, so it would be better if you label the actual name of the reaction.


remember that the type of reaction is addition, and the specific name of the reaction is hydrolysis.

Small technicality:

There is a difference between 'hydrolysis' and 'hydration'

In when water reacts in an addition reaction with a double bond, it is a 'hydration' reaction.

A + H2O --> B

In terms of organic chemistry, hydrolysis usually involve splitting of a larger molecule when reacting with water

A + H2O --> B + C

(and same goes for dehydration [A --> B + H2O] and condensation [A + B --> C + H2O])
These are not the most technically correct definitions, as hydrolysis doesn't necessarily split molecules in inorganic, physical and electrochemistry, but it will do

Heinemann still calls it hydrolysis for an addition reaction. Do we need to know about hydration?