Questions tagged [boiling-point]

The boiling point of a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid

Filter by
Sorted by
Tagged with
-1
votes
0answers
16 views

Describe with data why NH3, H2O and HF have higher boiling points than might be expected? [closed]

Please help me to answer this question. Describe with data why NH3, H2O and HF have higher boiling points than might be expected?
-2
votes
0answers
33 views

How to calculate the boiling point of a solution of eugenol in benzene? [closed]

Eugenol is the active ingredient in the oil of cloves used to relieve toothache. Calculate the boiling point of a solution in which $\pu{0.17 g}$ of eugenol $\ce{C10H12O2}$, is dissolved in $\pu{10.0 ...
4
votes
2answers
1k views

Why is latent heat of vaporization not exactly proportional to boiling point?

Latent heat of vaporization and boiling point are both chemical properties related to the bond strength of the molecule. In general, the higher the boiling point is, the higher the heat of ...
-1
votes
0answers
27 views

Normal melting point [closed]

Consider the following data for a substance: Critical point: 114.3 atm and 561°C Triple point: 0.108 atm and 114°C Normal melting point: 1.00 atm and 124°C What is the normal boiling point of the ...
2
votes
1answer
129 views

Why does Ethylene Glycol have higher boiling point than Propylene Glycol?

Looking at the two alcohols, both have hydrogen bonding and are singly bonded throughout the molecule. However, propylene glycol has a larger electron cloud which to my knowledge would increase its ...
2
votes
0answers
37 views

Why do fluoride molecules seem to have abnormally low boiling points?

As far as I know, to non-polar molecules like CF4 and C2H6, boiling point is mainly affected by the London dispersion force. As a result, molecules with more protons and electrons normally have higher ...
0
votes
0answers
35 views

How to find the normal boiling temperature if vapor pressure at any temperature is the only thing that can be usable?

Here is my program for calculating the vapor pressure of the Organic Chemicals using Antoine's Equation: ...
1
vote
0answers
19 views

How to find normal boiling temperature if vapor pressure is known in any temperature?

I can calculate the vapor pressure of the Acetone at any given temperature using the Antoine equation. Is it possible to find the normal boiling temperature of the Acetone? (It has to be done by just ...
-1
votes
0answers
46 views

Why does a covalent solid have a high melting point and boiling point as compared to an ionic solid? [duplicate]

Why does a covalent solid have a high melting point and boiling point as compared to an ionic solid? Shouldn't it be less than that of ionic solids since the coulombic forces in ionic solid is ...
1
vote
3answers
773 views

Why hydrogen bonds are stronger than Van der Waals forces?

Why the hydrogen bonds are more intense than Van der Waals forces in the case where the molecules with the Van der Waals forces have a stronger dipolar moment than the molecules with the hydrogen bond?...
0
votes
1answer
27 views

Why is Vapor Pressure of Liquid Equal to Ambient Pressure at Boiling?

What does phase change from liquid to gas have to do with equality of vapor pressure and ambient pressure? I understand that at higher pressures more kinetic energy is needed for molecules in liquid ...
10
votes
1answer
19k views

Caffeine boiling and melting points

According to both caffeine's PubChem page and ChemSpider page its boiling point lies at $\pu{173 °C}$ and its melting point at $\pu{\sim 235 °C}.$ How can it melt at that temperature if it already ...
0
votes
0answers
29 views

Why does 1,2-dihydroxybenzene have higher boiling point than monohydroxybenzene? [duplicate]

I studied that any kind of dihydroxybenzene has higher boiling point than monohydroxybenzene, and among the dihydroxybenzenes, I understood that because of inter molecular hydrogen bonding they have ...
1
vote
0answers
26 views

Comparison of boiling points of para-derivatives of phenol

The boiling points of four para-derivatives of phenol are: How can we compare the boiling points of p-nitrophenol and p-aminophenol? Apart from the hydroxyl group, p-nitrophenol has two oxygen atoms ...
2
votes
1answer
3k views

What effect on boiling and melting points does intramolecular hydrogen bonding have? [duplicate]

I know that intermolecular forces increase the boiling and melting point of a compound, but what is the effect of intramolecular forces on boiling and melting points? I found contradicting answers ...
0
votes
0answers
25 views

Why do amides have an inconsistent boiling point trend?

For many organic compounds such as alcohols and alkanes, the relationship between molar mass and boiling point is generally linear when graphed. However, amides have a very high boiling point and as ...
28
votes
1answer
13k views

Melting and boiling point trend in Group II

The following picture shows the melting and boiling point trends down group II elements. I have added question marks where the variability in data was rather disturbing (over two hundred degrees ...
0
votes
0answers
22 views

Why do compounds with low polarizability occur as gases at room temperature?

I've read in a textbook that in the fluorine atom, for example, high ionization energy reflects the fact that the electrons are tightly held. Thus compounds containing many fluorine atoms tend to have ...
0
votes
0answers
38 views

Why does a wooden spoon creates bubbles when put in hot oil?

This question might be a bit weird, but I just asked myself why a wooden cooking spoon creates bubbles when put in oil at about 170°C. This is a common trick to find out, if Oil has the right ...
0
votes
1answer
85 views

Why is boiling point of Ammonia greater than Arsine?

I have previously read that the boiling point of Stibane(SbH3) is greater than Ammonia(NH3) as ammonia is gas at room temperature and no hydrogen bonding exists in the gaseous form of NH3. Hence, as ...
6
votes
5answers
302 views

Is the average kinetic energy of evaporating water molecules (at room temperature) equivalent to the average kinetic energy of boiling water?

Purpose: On new year's eve, after a splendid red and an assortment of sumptuous repasts, I made a bold remark which, on further consideration, may turn out to be incorrect. Unless! Unless I can ...
9
votes
3answers
10k views

Experiment to prove that water has air

In elementary school, there was an experiment to show that water has dissolved air, which involved boiling some water and observing the drops at the surface of the container, and this proved that ...
1
vote
0answers
33 views

Variation of Boiling point with pressure from Clausius-Clapeyron equation

For a first-order phase transition such as water to steam , we write Clausius-Clapeyron equation as: $\frac{dP}{dT}= \frac{L}{T \Delta V}$ Now what I infer from this equation is that if the phase-...
9
votes
4answers
547 views

Is it true that an evaporating molecule has the same kinetic energy as a molecule in a pot of boiling water?

A molecule on the surface of room-temperature water shoots off the surface of said water, or in other words, it "evaporates." It does so because it gained kinetic energy ${x}$, and ${x}$ was great ...
1
vote
2answers
693 views

Why is the boiling point of trichlorofluoromethane lower than that of chloroform?

If $\ce{CFCl3}$ has a higher molar mass, how come $\ce{CHCl3}$ has a higher boiling point? $$ \begin{align} \mathrm{bp}(\ce{CFCl3}) &= \pu{23.77 °C} \\ \mathrm{bp}(\ce{CHCl3}) &= \pu{61.15 °C} ...
3
votes
1answer
203 views

Why is the boiling point of sugarcane juice lower than the boiling point of water?

As the boiling point is a colligative property, one would expect that the boiling point of sugarcane juice should be higher than pure water because Sugarcane juice contains water (75–85%), non-...
9
votes
2answers
3k views

How are the boiling points of Tungsten and other metals determined and proved?

The boiling point of Tungsten is 10,030 degrees Fahrenheit. How was this determined and proved? And more generally how are the boiling points of metals determined and proved? Is it really so simple ...
3
votes
1answer
101 views

Intermolecular forces of attraction between positional isomers of alcohols

This seemingly trivial question is as follows: Why is the boiling point of 1-butanol ($\ce {117.7 ^\circ C}$) higher than that of 2-butanol ($\ce {99 ^\circ C}$)? The only reason I can think of is ...
3
votes
0answers
55 views

Why ethyl cyanide and propanol have the same boiling point?

As I understand, the intermolecular forces of ethyl cyanide are of van der Waals nature (dipole-dipole) but in the propanol molecule there are hydrogen bonds which are in principle much stronger. Why ...
1
vote
1answer
104 views

Change in boiling and freezing point

I recently encountered a question while solving previous year question papers for JEE. This is a JEE 2005 question. The question demands to complete this statement: Equimolar solutions in the ...
-1
votes
1answer
40 views

Can you make n-Hexane a supercritical fluid? [closed]

When making aerogel using supercritical fluids the liquid in the gel is replaced by a gas. Can this be achieved using n-Hexane as the supercritical fluid? What would the resulting gas be? Would it be ...
0
votes
1answer
50 views

Melting point of objects and food

What is the melting point of egg yolk? Well, generally, when we break an egg, the yolk is in liquid state. After we pour it on a pan, the egg starts to cook and it hardens. My question is, can an egg ...
4
votes
1answer
3k views

Boil to dry 50 liters water

I would like to find out how long it would take to completely turn 50 litres of water to steam. Let's assume power of 2500 W and the water is already at boil. I am not very scientific so please ...
0
votes
1answer
308 views

Why is the temperature graph sigmoidal in simple distillation of components with very different bps?

I'm writing an organic chemistry lab report on distillation and I thought I understood this, but the more I look at my lab textbook, I realize I don't. My textbook 1 explains that the temperature of ...
3
votes
1answer
585 views

What is the temperature needed for a reflux using a mix of solvents as the reaction medium? [closed]

I had a quick query regarding the setup of a reaction. The procedure that I am working from states that I need to put my reaction mixture under reflux for 3 hours. The solvents used are diethyl ether (...
10
votes
3answers
6k views

Why is the boiling point of heavy water more than that of normal water?

In class we learnt that the London forces become stronger as the relative molecular mass increases. Not just as in organic chemistry but in things like the halogens. However, as I understand, the ...
4
votes
1answer
308 views

Why does dimethyl sulfoxide have higher boiling point than acetone?

They have very similar structure except for a central atom, but the difference in boiling points is very large $(\pu{186 ^\circ C}$ for DMSO and $\pu{56 ^\circ C}$ for acetone). How is central atom ...
4
votes
3answers
15k views

Why do the melting points of Group 15 elements increase upto Arsenic but then decrease upto Bismuth?

The boiling points of group 15 elements increase on going down the group (or, as size increases) but the same is not true for the melting points. The melting points increase from $\ce{N}$ to $\ce{As}$ ...
9
votes
1answer
1k views

Boiling point of alkynes from n = 2 to 10

From a video on organic chemistry, I found this table that shows the boiling point temperatures of alkynes $\ce{C_{n}H_{2n-2}}$ with $\,n=2...10$. $$\begin{array}{|c|c|c|c|} \hline n & t_\mathrm{...
0
votes
1answer
84 views

Compare the boiling points of isobutane and 1-butyne

Question: Compare between the boiling points of isobutane and 1-butyne The answer to this question is given as 1-butyne has higher boiling point than isobutane. My approach: I have been taught a few ...
22
votes
1answer
997 views

Anomalous boiling point of “iso-” alkanes

I was attempting to compare the boiling points of iso-hexane and 3-methylpentane. Boiling points of organic compounds depend upon three factors according to Master Organic Chemistry – 3 Trends That ...
0
votes
1answer
275 views

Latent heat of vaporization/evaporation

It's the amount of heat required for liquid ---> gas phase change of a substance at it's Boiling point. But my question is, does providing energy equivalent to latent heat of vaporization to a ...
1
vote
0answers
111 views

Boilling colloidal silver?

I have some colloidal silver that i bought from a shop. It is 18ppm, however, I need a higher PPM and I can't seem to buy it anywhere where I live. If I boil this colloidal silver, would it make the ...
1
vote
1answer
78 views

How does the polarizability of an apolar compound influence properties such as its boiling temperature? [closed]

I have understood that the more polar is a compound, the higher is its boiling temperature. But I would like to know what is the justification for this answer. I am new to chemistry so I would ...
7
votes
2answers
6k views

Melting and boiling points of benzene and fluorobenzene

This species is a derivative of benzene, with a single fluorine atom attached. Its melting point is -44 °C, which is lower than that of benzene, indicative of the remarkable effect of fluorination ...
2
votes
0answers
119 views

Order of boiling point of group 14 halides

Find out the species having lowest boiling point: (A) $\ce{SnCl4}$ (B) $\ce{GeCl4}$ (C) $\ce{SiCl4}$ (D) $\ce{CCl4}$ I have considered the inert pair effect of $\ce{Sn}$ here which will make the ...
4
votes
1answer
3k views

Does the boiling point of an aqueous solution depend on what the solute is?

Consider a situation where we have two aqueous solutions which have the same concentration (e.g. 1 M), but the solute is different. For example, one is a solution of glucose, and the other is a ...
-2
votes
1answer
334 views

Vapor Pressure and Boiling Point [duplicate]

I heard that the boiling point of a solution is the temperature where its vapor pressure at that temperature equals the atmospheric pressure at that temperature. Thus at higher altitudes, as the ...
-1
votes
1answer
29 views

Doubt about definition of boiling point [duplicate]

The definition of boiling point says boiling point is the temperature at which the vapour pressure of liquid becomes equal to vapour pressure of atmosphere. But how does the vapour pressure of the ...
0
votes
0answers
34 views

Difference in the boiling point of piperidine and cyclohexanamine

The reason that I believe must be the difference in the amount of hydrogen bonding formed by both of the compounds in the liquid . But I suspected that both must be having same amount of hydrogen ...

1
2 3 4 5 6