Tweeted twitter.com/StackChemistry/status/741788313493868544
    Bumped by Community user
4 changed wrong information
source | link

Molecule

Given this compound in an acidic medium, what would get protonated first? Would the double bond not get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the $\mathrm{p}K_\mathrm{a}$ value for the conjugate acid of an aldehyde, and it was around -10, which is pretty low; this suggests that the aldehyde would have a very low basicity.

Also ethenecarbocation had a $\mathrm{p}K_\mathrm{a}$ value of around 43-3.

Going by this information does it not make sense for a double bond to get protonated first?

On the other hand, the oxonium ion is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

Molecule

Given this compound in an acidic medium, what would get protonated first? Would the double bond not get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the $\mathrm{p}K_\mathrm{a}$ value for the conjugate acid of an aldehyde, and it was around -10, which is pretty low; this suggests that the aldehyde would have a very low basicity.

Also ethene had a $\mathrm{p}K_\mathrm{a}$ value of around 43.

Going by this information does it not make sense for a double bond to get protonated first?

On the other hand, the oxonium ion is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

Molecule

Given this compound in an acidic medium, what would get protonated first? Would the double bond not get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the $\mathrm{p}K_\mathrm{a}$ value for the conjugate acid of an aldehyde, and it was around -10, which is pretty low; this suggests that the aldehyde would have a very low basicity.

Also carbocation had a $\mathrm{p}K_\mathrm{a}$ value of around -3.

Going by this information does it not make sense for a double bond to get protonated first?

On the other hand, the oxonium ion is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

3 deleted 38 characters in body
source | link

enter image description hereMolecule

Given this compound in an acidic medium, what would get protonated first? Would not the double bond not get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the pka$\mathrm{p}K_\mathrm{a}$ value for the conjugate acid of an aldehyde, and it was around -10-10, which is pretty low, and hencelow; this suggests that the aldehyde would have a very low basicitylow basicity.

Also alkene (ethene)ethene had a pka$\mathrm{p}K_\mathrm{a}$ value of around 43.

Going by this information does it not make sense for a double bond to get protonated first?

ON the other hand, the oxonium ion, in this case is resonance stabilised, which would indicate that it is protonated in preference to the double bonds. On the other hand, the oxonium ion is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which of these reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates? Which reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

enter image description here

Given this compound in an acidic medium, what would get protonated first? Would not the double bond get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the pka value for the conjugate acid of aldehyde, and it was around -10, which is pretty low, and hence suggests that aldehyde would have a very low basicity

Also alkene (ethene) had a pka value of around 43.

Going by this information does it not make sense for a double bond to get protonated first?

ON the other hand, the oxonium ion, in this case is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which of these reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

Molecule

Given this compound in an acidic medium, what would get protonated first? Would the double bond not get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the $\mathrm{p}K_\mathrm{a}$ value for the conjugate acid of an aldehyde, and it was around -10, which is pretty low; this suggests that the aldehyde would have a very low basicity.

Also ethene had a $\mathrm{p}K_\mathrm{a}$ value of around 43.

Going by this information does it not make sense for a double bond to get protonated first?

On the other hand, the oxonium ion is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

2 deleted 4 characters in body; edited tags
source | link

enter image description here

Given this compound in an acidic medium  , what would get protonated first? Would not the double bond get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the pka value for the conjugate acid of aldehyde,and and it was around -10,which which is pretty low, and hence suggests that aldehyde would have a very low basicity

Also alkene (ethene) had a pka value of around 43.

Going by this information does it not make sense for a double bond to get protnatedprotonated first?

ON the other hand, the oxonium ion,in in this case is resonance stabilised  , which would indicate that it is protonated in preference to the double bonds.

Which of these reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

enter image description here

Given this compound in an acidic medium  , what would get protonated first? Would not the double bond get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the pka value for the conjugate acid of aldehyde,and it was around -10,which is pretty low, and hence suggests that aldehyde would have a very low basicity

Also alkene (ethene) had a pka value of around 43.

Going by this information does it not make sense for a double bond to get protnated first?

ON the other hand, the oxonium ion,in this case is resonance stabilised  , which would indicate that it is protonated in preference to the double bonds.

Which of these reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

enter image description here

Given this compound in an acidic medium, what would get protonated first? Would not the double bond get protonated preferentially, since oxygen is more electronegative than carbon and less willing to donate an electron pair for protonation?

I checked the pka value for the conjugate acid of aldehyde, and it was around -10, which is pretty low, and hence suggests that aldehyde would have a very low basicity

Also alkene (ethene) had a pka value of around 43.

Going by this information does it not make sense for a double bond to get protonated first?

ON the other hand, the oxonium ion, in this case is resonance stabilised, which would indicate that it is protonated in preference to the double bonds.

Which of these reasoning is correct? And more importantly, in these situations how are we supposed to predict which factor dominates?

1
source | link