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P-nitrophenol shows association due to H-bonding, and hence its molecular mass increases and colligative property decreases. So, its boiling point should decrease. So why is boiling point of p-nitrophenol more than that of o-nitrophenol?
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+ Physical chemistry
+ Chemistry
+ Colligative properties
+ Organic chemistry
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Kazakh Wazaky
P-nitrophenol shows association due to H-bonding, and hence its molecular mass increases and colligative property decreases. So, its boiling point should decrease. So why is boiling point of p-nitrophenol more than that of o-nitrophenol?
Boiling Point is a good indicator for the strength of intermolecular force because it tells us whether a substance has high or low intermolecular force.
For ex:if the boiling point of a substance is high that means the intermolecular forces are high too and vice versa.
As the intermolecular force is high the heat required to boil that substance is high too..
Boiling Point is a good indicator for the strength of intermolecular force because it tells us whether a substance has high or low intermolecular force.
For ex:if the boiling point of a substance is high that means the intermolecular forces are high too and vice versa.
As the intermolecular force is high the heat required to boil that substance is high too..
Adding ethanol to pure water will decrease the boiling point of the mixture. Adding more ethanol will continue to lower the b.p. until reaching the eutectic point. After that, more ethanol will raise the b.p. slightly until you have 100% alcohol. The eutectic point at 1 atm is about 83% C2H5OH.
Adding ethanol to pure water will decrease the boiling point of the mixture. Adding more ethanol will continue to lower the b.p. until reaching the eutectic point. After that, more ethanol will raise the b.p. slightly until you have 100% alcohol. The eutectic point at 1 atm is about 83% C2H5OH.
o- hydroxybenzaldehyde is stabilized by intramolecular hydrogen bonding and has lesser boiling point than p- hydroxybenzaldehyde. p- hydroxybenzaldehyde forms intermolecular hydrogen bonding and hence, has higher boiling point than o- hydroxybenzaldehyde.
o- hydroxybenzaldehyde is stabilized by intramolecular hydrogen bonding and has lesser boiling point than p- hydroxybenzaldehyde. p- hydroxybenzaldehyde forms intermolecular hydrogen bonding and hence, has higher boiling point than o- hydroxybenzaldehyde.
Para nitrophenol forms intermolecular hydrogen bond with the other molecules, but in Ortho nitrophenol the intramolecular hydrogen bond is formed. The hydrogen atom of hydroxyl group engaged in this bond cannot form intermolecular hydrogen bond with other molecule of Ortho nitrophenol.
Para nitrophenol forms intermolecular hydrogen bond with the other molecules, but in Ortho nitrophenol the intramolecular hydrogen bond is formed. The hydrogen atom of hydroxyl group engaged in this bond cannot form intermolecular hydrogen bond with other molecule of Ortho nitrophenol.
In fact, given INTERMOLECULAR HYDROGEN-BONDING, the normal boiling point SHOULD INCREASE …. i.e. there is an extra intermolecular force of attraction between MOLECULES of , transmitted by the H-bond…
On the other hand, while SHOULD engage in some hydrogen-bonding, this interaction is ext{INTRAMOLECULAR}… And what is the difference between , and ? For that matter, what are the normal boiling points of each species?
In fact, given INTERMOLECULAR HYDROGEN-BONDING, the normal boiling point SHOULD INCREASE …. i.e. there is an extra intermolecular force of attraction between MOLECULES of , transmitted by the H-bond…
On the other hand, while SHOULD engage in some hydrogen-bonding, this interaction is ext{INTRAMOLECULAR}… And what is the difference between , and ? For that matter, what are the normal boiling points of each species?
The simplest explanation is because furan has lower molecular mass (because O has lower mass than S) - heavier molecules need to have more energy to start freely moving with sufficient velocity to be in gas phase (this can be explained by formula kinetic energy = 1/2 × mass × velocity^2). Their polarities are similar enough that the effect of mass is more important.
The simplest explanation is because furan has lower molecular mass (because O has lower mass than S) - heavier molecules need to have more energy to start freely moving with sufficient velocity to be in gas phase (this can be explained by formula kinetic energy = 1/2 × mass × velocity^2). Their polarities are similar enough that the effect of mass is more important.
Intramolecular hydrogen bonding occurs within the molecule of o-Nitrophenol. The molecules of p-Nitrophenol get associated through intermolecular hydrogen bonding. So more heat is needed to break the hydrogen bonds present between the molecules of p-Nitrophenol. For this reason, p- Nitrophenol has a higher boiling point than o-Nitrophenol.
*Please note: This question can't be related to colligative properties. Colligative properties are shown only by the solutions.
Intramolecular hydrogen bonding occurs within the molecule of o-Nitrophenol. The molecules of p-Nitrophenol get associated through intermolecular hydrogen bonding. So more heat is needed to break the hydrogen bonds present between the molecules of p-Nitrophenol. For this reason, p- Nitrophenol has a higher boiling point than o-Nitrophenol.
*Please note: This question can't be related to colligative properties. Colligative properties are shown only by the solutions.
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Boiling Point is a good indicator for the strength of intermolecular force because it tells us whether a substance has high or low intermolecular force.
For ex:if the boiling point of a substance is high that means the intermolecular forces are high too and vice versa.
As the intermolecular force is high the heat required to boil that substance is high too..
Boiling Point is a good indicator for the strength of intermolecular force because it tells us whether a substance has high or low intermolecular force.
For ex:if the boiling point of a substance is high that means the intermolecular forces are high too and vice versa.
As the intermolecular force is high the heat required to boil that substance is high too..
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Adding ethanol to pure water will decrease the boiling point of the mixture. Adding more ethanol will continue to lower the b.p. until reaching the eutectic point. After that, more ethanol will raise the b.p. slightly until you have 100% alcohol. The eutectic point at 1 atm is about 83% C2H5OH.
Adding ethanol to pure water will decrease the boiling point of the mixture. Adding more ethanol will continue to lower the b.p. until reaching the eutectic point. After that, more ethanol will raise the b.p. slightly until you have 100% alcohol. The eutectic point at 1 atm is about 83% C2H5OH.
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o- hydroxybenzaldehyde is stabilized by intramolecular hydrogen bonding and has lesser boiling point than p- hydroxybenzaldehyde. p- hydroxybenzaldehyde forms intermolecular hydrogen bonding and hence, has higher boiling point than o- hydroxybenzaldehyde.
o- hydroxybenzaldehyde is stabilized by intramolecular hydrogen bonding and has lesser boiling point than p- hydroxybenzaldehyde. p- hydroxybenzaldehyde forms intermolecular hydrogen bonding and hence, has higher boiling point than o- hydroxybenzaldehyde.
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Para nitrophenol forms intermolecular hydrogen bond with the other molecules, but in Ortho nitrophenol the intramolecular hydrogen bond is formed. The hydrogen atom of hydroxyl group engaged in this bond cannot form intermolecular hydrogen bond with other molecule of Ortho nitrophenol.
Para nitrophenol forms intermolecular hydrogen bond with the other molecules, but in Ortho nitrophenol the intramolecular hydrogen bond is formed. The hydrogen atom of hydroxyl group engaged in this bond cannot form intermolecular hydrogen bond with other molecule of Ortho nitrophenol.
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In fact, given INTERMOLECULAR HYDROGEN-BONDING, the normal boiling point SHOULD INCREASE …. i.e. there is an extra intermolecular force of attraction between MOLECULES of , transmitted by the H-bond…
On the other hand, while SHOULD engage in some hydrogen-bonding, this interaction is ext{INTRAMOLECULAR}… And what is the difference between , and ? For that matter, what are the normal boiling points of each species?
In fact, given INTERMOLECULAR HYDROGEN-BONDING, the normal boiling point SHOULD INCREASE …. i.e. there is an extra intermolecular force of attraction between MOLECULES of , transmitted by the H-bond…
On the other hand, while SHOULD engage in some hydrogen-bonding, this interaction is ext{INTRAMOLECULAR}… And what is the difference between , and ? For that matter, what are the normal boiling points of each species?
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The simplest explanation is because furan has lower molecular mass (because O has lower mass than S) - heavier molecules need to have more energy to start freely moving with sufficient velocity to be in gas phase (this can be explained by formula kinetic energy = 1/2 × mass × velocity^2). Their polarities are similar enough that the effect of mass is more important.
The simplest explanation is because furan has lower molecular mass (because O has lower mass than S) - heavier molecules need to have more energy to start freely moving with sufficient velocity to be in gas phase (this can be explained by formula kinetic energy = 1/2 × mass × velocity^2). Their polarities are similar enough that the effect of mass is more important.
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Higher boiling points will correspond to stronger intermolecular forces. Go through the list above.
1.None of these have hydrogen bonding.
2.None of these have dipoles.
3.Bigger molecules will have stronger London dispersion forces. So I2 has the strongest forces,
and F2 will have the weakest. Correspondingly, I2 will have the highest boiling point and F2 will have the lowest boiling point.
Answer: F2 , Cl2 , Br2 , I2
Higher boiling points will correspond to stronger intermolecular forces. Go through the list above.
1.None of these have hydrogen bonding.
2.None of these have dipoles.
3.Bigger molecules will have stronger London dispersion forces. So I2 has the strongest forces,
and F2 will have the weakest. Correspondingly, I2 will have the highest boiling point and F2 will have the lowest boiling point.
Answer: F2 , Cl2 , Br2 , I2
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Intramolecular hydrogen bonding occurs within the molecule of o-Nitrophenol. The molecules of p-Nitrophenol get associated through intermolecular hydrogen bonding. So more heat is needed to break the hydrogen bonds present between the molecules of p-Nitrophenol. For this reason, p- Nitrophenol has a higher boiling point than o-Nitrophenol.
*Please note: This question can't be related to colligative properties. Colligative properties are shown only by the solutions.
Intramolecular hydrogen bonding occurs within the molecule of o-Nitrophenol. The molecules of p-Nitrophenol get associated through intermolecular hydrogen bonding. So more heat is needed to break the hydrogen bonds present between the molecules of p-Nitrophenol. For this reason, p- Nitrophenol has a higher boiling point than o-Nitrophenol.
*Please note: This question can't be related to colligative properties. Colligative properties are shown only by the solutions.
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