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the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling.

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  the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling. Serg io <invaalid@invalid.com> - 2017-07-20 20:08 -0500
    Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. James McGinn <jimmcginn9@gmail.com> - 2017-07-20 18:18 -0700
      Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. benj <benj@nobody.net> - 2017-07-20 21:46 -0400
        Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. James McGinn <jimmcginn9@gmail.com> - 2017-07-20 22:14 -0700
          Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. Solving Tornadoes <solvingtornadoes@gmail.com> - 2017-07-25 18:25 -0700
        Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. Serg io <invaalid@invalid.com> - 2017-07-21 07:49 -0500
          Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. Solving Tornadoes <solvingtornadoes@gmail.com> - 2017-07-25 18:19 -0700
        Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. James McGinn <jimmcginn9@gmail.com> - 2017-07-22 08:42 -0700
        Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. James McGinn <jimmcginn9@gmail.com> - 2017-07-22 17:28 -0700
    Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling. benj <benj@nobody.net> - 2017-07-20 21:36 -0400
    Re: the boiling point is simply the temperature such that the  vapor,pressure equals total pressure, at whatever total pressure your  system,is at. At normal atmospheric pressure, the vapor pressure of water  is,equal to atmospheric pressure at 100C. This means instead of gas  water,molecules only being able to self-diffuse through the atmosphere,  they,can actually displace the atmosphere, and you get the bubbles  and,roiling of boiling. The Starmaker <starmaker@ix.netcom.com> - 2017-07-20 20:35 -0700
      Re: the boiling point is simply the temperature such that the  vapor,pressure equals total pressure, at whatever total pressure your  system,is at. At normal atmospheric pressure, the vapor pressure of water  is,equal to atmospheric pressure at 100C. James McGinn <jimmcginn9@gmail.com> - 2017-07-20 22:15 -0700
    Re: the boiling point is simply the temperature such that the  vapor,pressure equals total pressure, at whatever total pressure your  system,is at. At normal atmospheric pressure, the vapor pressure of water  is,equal to atmospheric pressure at 100C. This means instead of gas  water,molecules only being able to self-diffuse through the atmosphere,  they,can actually displace the atmosphere, and you get the bubbles  and,roiling of boiling. The Starmaker <starmaker@ix.netcom.com> - 2017-07-20 20:49 -0700
    Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling. Serg io <invaalid@invalid.com> - 2017-07-25 15:13 -0500

#641609 — the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling.

Glad you asked Claudius, many are so confused like you are on this subject.

Even though 100°C is the actual temperature needed for water to boil,
the nature of matter is such that even under that temperature, some
molecules have enough kinetic energy to convert to gaseous form.
Temperature is merely the average kinetic energy of a system, so some
molecules are above that temperature and some are below at all times.
Under 100°C, say at 80°C, some molecules would still have enough kinetic
energy to convert to gaseous form.

This is why water still evaporates over time, albeit very very slowly,
from say, a puddle, on a cooler day. Increasing temperature just
increases the rate of a favorable reaction that is naturally
occurring/provides the conditions for it to spontaneously occur.
Reactions favor the direction that increases the number of micro states
available to the system (think in terms of wanting personal space - in
general, gaseous form is more "comfortable" for a compound vs. being
smooshed as a liquid or even more smooshed as a solid), some reactions
just don't happen spontaneously without certain conditions or a
catalyst, i.e. a specific temperature.

The "steam" you see is a mist* of the gaseous particles being condensed
into tiny liquid particles suspended in the air, which is cooler than
the system the gas just left.

For any substance, the energies of the molecules are spread out in a
bell curve. So while the mean energy (what we call temperature) is 0°C
or less, a proportion of molecules have energies that would correspond
to 10°C or even 100°C. This is given by the formula:

fraction of molecules with energy greater than ε = e-ε/kT where k is a
constant, the Boltzmann constant, and T is the current temperature in
Kelvin (Celsius + 273). e is 2.7182818.....

Since it's exponential, the proportion drops of rapidly though. The
energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
into your calculator. It comes out around 12.8%, so that many molecules
behave like they have a temperature of 100°C.

PS: for physicists: I understand that 1.5k*373 is not the same as the
energy needed to sublimate. This is just to get across the idea that a
significant proportion of molecules have much higher energy than the mean.

All solids and liquids have something called a "vapor pressure", which
is essentially the average amount of gas molecules existing near the
surface of the solid or liquid. If this vapor pressure of that gas at
the puddle surface is higher than the number of molecules (of that gas)
existing in the ambient, it will diffuse into the ambient, and there is
a net transfer from the puddle to the atmosphere, hence the puddle shrinks.

This is why puddles evaporate quicker on drier days, and slower on humid
days. And if the temperature drops (vapor pressure depends on
temperature) and ambient humidity rises, this can go the other
direction, and you get dew.

[toc] | [next] | [standalone]

#641611 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> Glad you asked Claudius, many are so confused like you are on this subject.
> 
> Even though 100°C is the actual temperature needed for water to boil,
> the nature of matter is such that even under that temperature, some
> molecules have enough kinetic energy to convert to gaseous form.
> Temperature is merely the average kinetic energy of a system, so some
> molecules are above that temperature and some are below at all times.
> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> energy to convert to gaseous form.

Wrong.


> 
> This is why water still evaporates over time, albeit very very slowly,
> from say, a puddle, on a cooler day. Increasing temperature just
> increases the rate of a favorable reaction that is naturally
> occurring/provides the conditions for it to spontaneously occur.
> Reactions favor the direction that increases the number of micro states
> available to the system (think in terms of wanting personal space - in
> general, gaseous form is more "comfortable" for a compound vs. being
> smooshed as a liquid or even more smooshed as a solid), some reactions
> just don't happen spontaneously without certain conditions or a
> catalyst, i.e. a specific temperature.
> 
> The "steam" you see is a mist* of the gaseous particles being condensed
> into tiny liquid particles suspended in the air, which is cooler than
> the system the gas just left.
> 
> For any substance, the energies of the molecules are spread out in a
> bell curve. So while the mean energy (what we call temperature) is 0°C
> or less, a proportion of molecules have energies that would correspond
> to 10°C or even 100°C. This is given by the formula:
> 
> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> constant, the Boltzmann constant, and T is the current temperature in
> Kelvin (Celsius + 273). e is 2.7182818.....
> 
> Since it's exponential, the proportion drops of rapidly though. The
> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> into your calculator. It comes out around 12.8%, so that many molecules
> behave like they have a temperature of 100°C.
> 
> PS: for physicists: I understand that 1.5k*373 is not the same as the
> energy needed to sublimate. This is just to get across the idea that a
> significant proportion of molecules have much higher energy than the mean.
> 
> All solids and liquids have something called a "vapor pressure", which
> is essentially the average amount of gas molecules existing near the
> surface of the solid or liquid. If this vapor pressure of that gas at
> the puddle surface is higher than the number of molecules (of that gas)
> existing in the ambient, it will diffuse into the ambient, and there is
> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
> 
> This is why puddles evaporate quicker on drier days, and slower on humid
> days. And if the temperature drops (vapor pressure depends on
> temperature) and ambient humidity rises, this can go the other
> direction, and you get dew.

[toc] | [prev] | [next] | [standalone]

#641622 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On 7/20/2017 9:18 PM, James McGinn wrote:
> On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
>> Glad you asked Claudius, many are so confused like you are on this subject.
>>
>> Even though 100°C is the actual temperature needed for water to boil,
>> the nature of matter is such that even under that temperature, some
>> molecules have enough kinetic energy to convert to gaseous form.
>> Temperature is merely the average kinetic energy of a system, so some
>> molecules are above that temperature and some are below at all times.
>> Under 100°C, say at 80°C, some molecules would still have enough kinetic
>> energy to convert to gaseous form.
> 
> Wrong.

Hey , McFly, I've ignored you up to now, but are you SURE you want to 
say something this stupid? Please think about it.


>> This is why water still evaporates over time, albeit very very slowly,
>> from say, a puddle, on a cooler day. Increasing temperature just
>> increases the rate of a favorable reaction that is naturally
>> occurring/provides the conditions for it to spontaneously occur.
>> Reactions favor the direction that increases the number of micro states
>> available to the system (think in terms of wanting personal space - in
>> general, gaseous form is more "comfortable" for a compound vs. being
>> smooshed as a liquid or even more smooshed as a solid), some reactions
>> just don't happen spontaneously without certain conditions or a
>> catalyst, i.e. a specific temperature.
>>
>> The "steam" you see is a mist* of the gaseous particles being condensed
>> into tiny liquid particles suspended in the air, which is cooler than
>> the system the gas just left.
>>
>> For any substance, the energies of the molecules are spread out in a
>> bell curve. So while the mean energy (what we call temperature) is 0°C
>> or less, a proportion of molecules have energies that would correspond
>> to 10°C or even 100°C. This is given by the formula:
>>
>> fraction of molecules with energy greater than ε = e-ε/kT where k is a
>> constant, the Boltzmann constant, and T is the current temperature in
>> Kelvin (Celsius + 273). e is 2.7182818.....
>>
>> Since it's exponential, the proportion drops of rapidly though. The
>> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
>> into your calculator. It comes out around 12.8%, so that many molecules
>> behave like they have a temperature of 100°C.
>>
>> PS: for physicists: I understand that 1.5k*373 is not the same as the
>> energy needed to sublimate. This is just to get across the idea that a
>> significant proportion of molecules have much higher energy than the mean.
>>
>> All solids and liquids have something called a "vapor pressure", which
>> is essentially the average amount of gas molecules existing near the
>> surface of the solid or liquid. If this vapor pressure of that gas at
>> the puddle surface is higher than the number of molecules (of that gas)
>> existing in the ambient, it will diffuse into the ambient, and there is
>> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
>>
>> This is why puddles evaporate quicker on drier days, and slower on humid
>> days. And if the temperature drops (vapor pressure depends on
>> temperature) and ambient humidity rises, this can go the other
>> direction, and you get dew.
> 

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#641633 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 6:46:24 PM UTC-7, benj wrote:
> On 7/20/2017 9:18 PM, James McGinn wrote:
> > On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> >> Glad you asked Claudius, many are so confused like you are on this subject.
> >>
> >> Even though 100°C is the actual temperature needed for water to boil,
> >> the nature of matter is such that even under that temperature, some
> >> molecules have enough kinetic energy to convert to gaseous form.
> >> Temperature is merely the average kinetic energy of a system, so some
> >> molecules are above that temperature and some are below at all times.
> >> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> >> energy to convert to gaseous form.
> > 
> > Wrong.
> 
> Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> say something this stupid? Please think about it.

Uh, it's a boiling point.  It's not a boiling continuum.

Find another hobby.

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#642537 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 10:14:29 PM UTC-7, James McGinn wrote:
> On Thursday, July 20, 2017 at 6:46:24 PM UTC-7, benj wrote:
> > On 7/20/2017 9:18 PM, James McGinn wrote:
> > > On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> > >> Glad you asked Claudius, many are so confused like you are on this subject.
> > >>
> > >> Even though 100°C is the actual temperature needed for water to boil,
> > >> the nature of matter is such that even under that temperature, some
> > >> molecules have enough kinetic energy to convert to gaseous form.
> > >> Temperature is merely the average kinetic energy of a system, so some
> > >> molecules are above that temperature and some are below at all times.
> > >> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> > >> energy to convert to gaseous form.
> > > 
> > > Wrong.
> > 
> > Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> > say something this stupid? Please think about it.
> 
> Uh, it's a boiling point.  It's not a boiling continuum.

ROTFL!!!

Trolls are so clueless.

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#641656 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On 7/20/2017 8:46 PM, benj wrote:
> On 7/20/2017 9:18 PM, James McGinn wrote:
>> On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
>>> Glad you asked Claudius, many are so confused like you are on this 
>>> subject.
>>>
>>> Even though 100°C is the actual temperature needed for water to boil,
>>> the nature of matter is such that even under that temperature, some
>>> molecules have enough kinetic energy to convert to gaseous form.
>>> Temperature is merely the average kinetic energy of a system, so some
>>> molecules are above that temperature and some are below at all times.
>>> Under 100°C, say at 80°C, some molecules would still have enough kinetic
>>> energy to convert to gaseous form.
>>
>> Wrong.
> 
> Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> say something this stupid? Please think about it.


     that is the key thing McFly fails to understand.

liquids are simply collection of molecules with a wide range of kinetic 
energies.

there is no "magic" number where all the molecules decide to be a 
liquid.   [counter to what McGinn espouses]

How would they know?  would they look it up in a book?  would they 
google for it ?


McGinn never states how his theory works.  (magic happens here)

> 
> 
>>> This is why water still evaporates over time, albeit very very slowly,
>>> from say, a puddle, on a cooler day. Increasing temperature just
>>> increases the rate of a favorable reaction that is naturally
>>> occurring/provides the conditions for it to spontaneously occur.
>>> Reactions favor the direction that increases the number of micro states
>>> available to the system (think in terms of wanting personal space - in
>>> general, gaseous form is more "comfortable" for a compound vs. being
>>> smooshed as a liquid or even more smooshed as a solid), some reactions
>>> just don't happen spontaneously without certain conditions or a
>>> catalyst, i.e. a specific temperature.
>>>
>>> The "steam" you see is a mist* of the gaseous particles being condensed
>>> into tiny liquid particles suspended in the air, which is cooler than
>>> the system the gas just left.
>>>
>>> For any substance, the energies of the molecules are spread out in a
>>> bell curve. So while the mean energy (what we call temperature) is 0°C
>>> or less, a proportion of molecules have energies that would correspond
>>> to 10°C or even 100°C. This is given by the formula:
>>>
>>> fraction of molecules with energy greater than ε = e-ε/kT where k is a
>>> constant, the Boltzmann constant, and T is the current temperature in
>>> Kelvin (Celsius + 273). e is 2.7182818.....
>>>
>>> Since it's exponential, the proportion drops of rapidly though. The
>>> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
>>> into your calculator. It comes out around 12.8%, so that many molecules
>>> behave like they have a temperature of 100°C.
>>>
>>> PS: for physicists: I understand that 1.5k*373 is not the same as the
>>> energy needed to sublimate. This is just to get across the idea that a
>>> significant proportion of molecules have much higher energy than the 
>>> mean.
>>>
>>> All solids and liquids have something called a "vapor pressure", which
>>> is essentially the average amount of gas molecules existing near the
>>> surface of the solid or liquid. If this vapor pressure of that gas at
>>> the puddle surface is higher than the number of molecules (of that gas)
>>> existing in the ambient, it will diffuse into the ambient, and there is
>>> a net transfer from the puddle to the atmosphere, hence the puddle 
>>> shrinks.
>>>
>>> This is why puddles evaporate quicker on drier days, and slower on humid
>>> days. And if the temperature drops (vapor pressure depends on
>>> temperature) and ambient humidity rises, this can go the other
>>> direction, and you get dew.
>>
> 

[toc] | [prev] | [next] | [standalone]

#642531 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Friday, July 21, 2017 at 5:49:51 AM UTC-7, Serg io wrote:
> On 7/20/2017 8:46 PM, benj wrote:
> > On 7/20/2017 9:18 PM, James McGinn wrote:
> >> On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> >>> Glad you asked Claudius, many are so confused like you are on this 
> >>> subject.
> >>>
> >>> Even though 100°C is the actual temperature needed for water to boil,
> >>> the nature of matter is such that even under that temperature, some
> >>> molecules have enough kinetic energy to convert to gaseous form.
> >>> Temperature is merely the average kinetic energy of a system, so some
> >>> molecules are above that temperature and some are below at all times.
> >>> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> >>> energy to convert to gaseous form.
> >>
> >> Wrong.
> > 
> > Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> > say something this stupid? Please think about it.
> 
> 
>      that is the key thing McFly fails to understand.
> 
> liquids are simply collection of molecules with a wide range of kinetic 
> energies.
> 
> there is no "magic" number where all the molecules decide to be a 
> liquid.   [counter to what McGinn espouses]

Why would the people that constructed steam tables be lying?



> 
> How would they know?  would they look it up in a book?  would they 
> google for it ?
> 
> 
> McGinn never states how his theory works.  (magic happens here)
> 
> > 
> > 
> >>> This is why water still evaporates over time, albeit very very slowly,
> >>> from say, a puddle, on a cooler day. Increasing temperature just
> >>> increases the rate of a favorable reaction that is naturally
> >>> occurring/provides the conditions for it to spontaneously occur.
> >>> Reactions favor the direction that increases the number of micro states
> >>> available to the system (think in terms of wanting personal space - in
> >>> general, gaseous form is more "comfortable" for a compound vs. being
> >>> smooshed as a liquid or even more smooshed as a solid), some reactions
> >>> just don't happen spontaneously without certain conditions or a
> >>> catalyst, i.e. a specific temperature.
> >>>
> >>> The "steam" you see is a mist* of the gaseous particles being condensed
> >>> into tiny liquid particles suspended in the air, which is cooler than
> >>> the system the gas just left.
> >>>
> >>> For any substance, the energies of the molecules are spread out in a
> >>> bell curve. So while the mean energy (what we call temperature) is 0°C
> >>> or less, a proportion of molecules have energies that would correspond
> >>> to 10°C or even 100°C. This is given by the formula:
> >>>
> >>> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> >>> constant, the Boltzmann constant, and T is the current temperature in
> >>> Kelvin (Celsius + 273). e is 2.7182818.....
> >>>
> >>> Since it's exponential, the proportion drops of rapidly though. The
> >>> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> >>> into your calculator. It comes out around 12.8%, so that many molecules
> >>> behave like they have a temperature of 100°C.
> >>>
> >>> PS: for physicists: I understand that 1.5k*373 is not the same as the
> >>> energy needed to sublimate. This is just to get across the idea that a
> >>> significant proportion of molecules have much higher energy than the 
> >>> mean.
> >>>
> >>> All solids and liquids have something called a "vapor pressure", which
> >>> is essentially the average amount of gas molecules existing near the
> >>> surface of the solid or liquid. If this vapor pressure of that gas at
> >>> the puddle surface is higher than the number of molecules (of that gas)
> >>> existing in the ambient, it will diffuse into the ambient, and there is
> >>> a net transfer from the puddle to the atmosphere, hence the puddle 
> >>> shrinks.
> >>>
> >>> This is why puddles evaporate quicker on drier days, and slower on humid
> >>> days. And if the temperature drops (vapor pressure depends on
> >>> temperature) and ambient humidity rises, this can go the other
> >>> direction, and you get dew.
> >>
> >

[toc] | [prev] | [next] | [standalone]

#641822 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 6:46:24 PM UTC-7, benj wrote:
> On 7/20/2017 9:18 PM, James McGinn wrote:
> > On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> >> Glad you asked Claudius, many are so confused like you are on this subject.
> >>
> >> Even though 100°C is the actual temperature needed for water to boil,
> >> the nature of matter is such that even under that temperature, some
> >> molecules have enough kinetic energy to convert to gaseous form.
> >> Temperature is merely the average kinetic energy of a system, so some
> >> molecules are above that temperature and some are below at all times.
> >> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> >> energy to convert to gaseous form.
> > 
> > Wrong.
> 
> Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> say something this stupid? Please think about it.

I didn't know you were ingoring me.  I thought I was just lucky.

You are an idiot with nothing to add to the conversation, go play with HVAC

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#641892 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 6:46:24 PM UTC-7, benj wrote:
> On 7/20/2017 9:18 PM, James McGinn wrote:
> > On Thursday, July 20, 2017 at 6:08:31 PM UTC-7, Serg io wrote:
> >> Glad you asked Claudius, many are so confused like you are on this subject.
> >>
> >> Even though 100°C is the actual temperature needed for water to boil,
> >> the nature of matter is such that even under that temperature, some
> >> molecules have enough kinetic energy to convert to gaseous form.
> >> Temperature is merely the average kinetic energy of a system, so some
> >> molecules are above that temperature and some are below at all times.
> >> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> >> energy to convert to gaseous form.
> > 
> > Wrong.
> 
> Hey , McFly, I've ignored you up to now, but are you SURE you want to 
> say something this stupid? Please think about it.

I am sure that . . . 

. . . you got nothing!!!

James McGinn / Solving Tornadoes

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#641617

On 7/20/2017 9:08 PM, Serg io wrote:
> Glad you asked Claudius, many are so confused like you are on this subject.
> 
> Even though 100°C is the actual temperature needed for water to boil,
> the nature of matter is such that even under that temperature, some
> molecules have enough kinetic energy to convert to gaseous form.
> Temperature is merely the average kinetic energy of a system, so some
> molecules are above that temperature and some are below at all times.
> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> energy to convert to gaseous form.

This is called "cold Steam" Sergio!

> This is why water still evaporates over time, albeit very very slowly,
> from say, a puddle, on a cooler day. Increasing temperature just
> increases the rate of a favorable reaction that is naturally
> occurring/provides the conditions for it to spontaneously occur.
> Reactions favor the direction that increases the number of micro states
> available to the system (think in terms of wanting personal space - in
> general, gaseous form is more "comfortable" for a compound vs. being
> smooshed as a liquid or even more smooshed as a solid), some reactions
> just don't happen spontaneously without certain conditions or a
> catalyst, i.e. a specific temperature.

More temperature, more cold steam. Simple! Eventually with enough 
temperature cold steam becomes hot steam!


> The "steam" you see is a mist* of the gaseous particles being condensed
> into tiny liquid particles suspended in the air, which is cooler than
> the system the gas just left.


And hot steam transforms into cold steam! This theory is now getting 
somewhere!

> For any substance, the energies of the molecules are spread out in a
> bell curve. So while the mean energy (what we call temperature) is 0°C
> or less, a proportion of molecules have energies that would correspond
> to 10°C or even 100°C. This is given by the formula:
> 
> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> constant, the Boltzmann constant, and T is the current temperature in
> Kelvin (Celsius + 273). e is 2.7182818.....

The dumber (we term them "slower") particles are out on the wings of the 
Bell Curve just like with people.

> Since it's exponential, the proportion drops of rapidly though. The
> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> into your calculator. It comes out around 12.8%, so that many molecules
> behave like they have a temperature of 100°C.
> 
> PS: for physicists: I understand that 1.5k*373 is not the same as the
> energy needed to sublimate. This is just to get across the idea that a
> significant proportion of molecules have much higher energy than the mean.

It's OK. They found that nobody ever used math once they got out of High 
School so they just stopped teaching it as a waste of time.

> All solids and liquids have something called a "vapor pressure", which
> is essentially the average amount of gas molecules existing near the
> surface of the solid or liquid. If this vapor pressure of that gas at
> the puddle surface is higher than the number of molecules (of that gas)
> existing in the ambient, it will diffuse into the ambient, and there is
> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.

This is true. Especially for solids. For example valuable items like 
wallets, coins, money and precious metals have a very high vapor 
pressure. They will rapidly disappear from any place where they are left 
unattended for a period of time. Rule of physics: The more valuable the 
solid the higher the vapor pressure!

> This is why puddles evaporate quicker on drier days, and slower on humid
> days. And if the temperature drops (vapor pressure depends on
> temperature) and ambient humidity rises, this can go the other
> direction, and you get dew.

Dew is just cold steam returning "home". I love science, don't you?

[toc] | [prev] | [next] | [standalone]

#641627 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling.

What I don't unnderstand is why do you pretend to do the explaining? Why the cut-and-paste?

https://www.quora.com/Why-does-steam-come-when-you-boil-water#!n=18

(see Shams Shimu, Still learning..
Answered Feb 3, 2016)


https://www.reddit.com/r/askscience/comments/2ng06u/why_does_my_hot_drink_have_steam_rising_from_it/





Serg io wrote:
> 
> Glad you asked Claudius, many are so confused like you are on this subject.
> 
> Even though 100°C is the actual temperature needed for water to boil,
> the nature of matter is such that even under that temperature, some
> molecules have enough kinetic energy to convert to gaseous form.
> Temperature is merely the average kinetic energy of a system, so some
> molecules are above that temperature and some are below at all times.
> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> energy to convert to gaseous form.
> 
> This is why water still evaporates over time, albeit very very slowly,
> from say, a puddle, on a cooler day. Increasing temperature just
> increases the rate of a favorable reaction that is naturally
> occurring/provides the conditions for it to spontaneously occur.
> Reactions favor the direction that increases the number of micro states
> available to the system (think in terms of wanting personal space - in
> general, gaseous form is more "comfortable" for a compound vs. being
> smooshed as a liquid or even more smooshed as a solid), some reactions
> just don't happen spontaneously without certain conditions or a
> catalyst, i.e. a specific temperature.
> 
> The "steam" you see is a mist* of the gaseous particles being condensed
> into tiny liquid particles suspended in the air, which is cooler than
> the system the gas just left.
> 
> For any substance, the energies of the molecules are spread out in a
> bell curve. So while the mean energy (what we call temperature) is 0°C
> or less, a proportion of molecules have energies that would correspond
> to 10°C or even 100°C. This is given by the formula:
> 
> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> constant, the Boltzmann constant, and T is the current temperature in
> Kelvin (Celsius + 273). e is 2.7182818.....
> 
> Since it's exponential, the proportion drops of rapidly though. The
> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> into your calculator. It comes out around 12.8%, so that many molecules
> behave like they have a temperature of 100°C.
> 
> PS: for physicists: I understand that 1.5k*373 is not the same as the
> energy needed to sublimate. This is just to get across the idea that a
> significant proportion of molecules have much higher energy than the mean.
> 
> All solids and liquids have something called a "vapor pressure", which
> is essentially the average amount of gas molecules existing near the
> surface of the solid or liquid. If this vapor pressure of that gas at
> the puddle surface is higher than the number of molecules (of that gas)
> existing in the ambient, it will diffuse into the ambient, and there is
> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
> 
> This is why puddles evaporate quicker on drier days, and slower on humid
> days. And if the temperature drops (vapor pressure depends on
> temperature) and ambient humidity rises, this can go the other
> direction, and you get dew.

[toc] | [prev] | [next] | [standalone]

#641634 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C.

On Thursday, July 20, 2017 at 8:34:25 PM UTC-7, The Starmaker wrote:
> What I don't unnderstand is why do you pretend to do the explaining? Why the cut-and-paste?
> 
> https://www.quora.com/Why-does-steam-come-when-you-boil-water#!n=18
> 
> (see Shams Shimu, Still learning..
> Answered Feb 3, 2016)
> 
> 
> https://www.reddit.com/r/askscience/comments/2ng06u/why_does_my_hot_drink_have_steam_rising_from_it/
> 
> 
> 
> 
> 
> Serg io wrote:
> > 
> > Glad you asked Claudius, many are so confused like you are on this subject.
> > 
> > Even though 100°C is the actual temperature needed for water to boil,
> > the nature of matter is such that even under that temperature, some
> > molecules have enough kinetic energy to convert to gaseous form.
> > Temperature is merely the average kinetic energy of a system, so some
> > molecules are above that temperature and some are below at all times.
> > Under 100°C, say at 80°C, some molecules would still have enough kinetic
> > energy to convert to gaseous form.
> > 
> > This is why water still evaporates over time, albeit very very slowly,
> > from say, a puddle, on a cooler day. Increasing temperature just
> > increases the rate of a favorable reaction that is naturally
> > occurring/provides the conditions for it to spontaneously occur.
> > Reactions favor the direction that increases the number of micro states
> > available to the system (think in terms of wanting personal space - in
> > general, gaseous form is more "comfortable" for a compound vs. being
> > smooshed as a liquid or even more smooshed as a solid), some reactions
> > just don't happen spontaneously without certain conditions or a
> > catalyst, i.e. a specific temperature.
> > 
> > The "steam" you see is a mist* of the gaseous particles being condensed
> > into tiny liquid particles suspended in the air, which is cooler than
> > the system the gas just left.
> > 
> > For any substance, the energies of the molecules are spread out in a
> > bell curve. So while the mean energy (what we call temperature) is 0°C
> > or less, a proportion of molecules have energies that would correspond
> > to 10°C or even 100°C. This is given by the formula:
> > 
> > fraction of molecules with energy greater than ε = e-ε/kT where k is a
> > constant, the Boltzmann constant, and T is the current temperature in
> > Kelvin (Celsius + 273). e is 2.7182818.....
> > 
> > Since it's exponential, the proportion drops of rapidly though. The
> > energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> > into your calculator. It comes out around 12.8%, so that many molecules
> > behave like they have a temperature of 100°C.
> > 
> > PS: for physicists: I understand that 1.5k*373 is not the same as the
> > energy needed to sublimate. This is just to get across the idea that a
> > significant proportion of molecules have much higher energy than the mean.
> > 
> > All solids and liquids have something called a "vapor pressure", which
> > is essentially the average amount of gas molecules existing near the
> > surface of the solid or liquid. If this vapor pressure of that gas at
> > the puddle surface is higher than the number of molecules (of that gas)
> > existing in the ambient, it will diffuse into the ambient, and there is
> > a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
> > 
> > This is why puddles evaporate quicker on drier days, and slower on humid
> > days. And if the temperature drops (vapor pressure depends on
> > temperature) and ambient humidity rises, this can go the other
> > direction, and you get dew.

When you cut and paste you prove you are an idiot.

[toc] | [prev] | [next] | [standalone]

#641628 — Re: the boiling point is simply the temperature such that the vapor,pressure equals total pressure, at whatever total pressure your system,is at. At normal atmospheric pressure, the vapor pressure of water is,equal to atmospheric pressure at 100C. This means instead of gas water,molecules only being able to self-diffuse through the atmosphere, they,can actually displace the atmosphere, and you get the bubbles and,roiling of boiling.

http://rebrn.com/re/why-does-my-hot-drink-have-steam-rising-from-it-when-it-is-below-353510/


Serg io wrote:
> 
> Glad you asked Claudius, many are so confused like you are on this subject.
> 
> Even though 100°C is the actual temperature needed for water to boil,
> the nature of matter is such that even under that temperature, some
> molecules have enough kinetic energy to convert to gaseous form.
> Temperature is merely the average kinetic energy of a system, so some
> molecules are above that temperature and some are below at all times.
> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> energy to convert to gaseous form.
> 
> This is why water still evaporates over time, albeit very very slowly,
> from say, a puddle, on a cooler day. Increasing temperature just
> increases the rate of a favorable reaction that is naturally
> occurring/provides the conditions for it to spontaneously occur.
> Reactions favor the direction that increases the number of micro states
> available to the system (think in terms of wanting personal space - in
> general, gaseous form is more "comfortable" for a compound vs. being
> smooshed as a liquid or even more smooshed as a solid), some reactions
> just don't happen spontaneously without certain conditions or a
> catalyst, i.e. a specific temperature.
> 
> The "steam" you see is a mist* of the gaseous particles being condensed
> into tiny liquid particles suspended in the air, which is cooler than
> the system the gas just left.
> 
> For any substance, the energies of the molecules are spread out in a
> bell curve. So while the mean energy (what we call temperature) is 0°C
> or less, a proportion of molecules have energies that would correspond
> to 10°C or even 100°C. This is given by the formula:
> 
> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> constant, the Boltzmann constant, and T is the current temperature in
> Kelvin (Celsius + 273). e is 2.7182818.....
> 
> Since it's exponential, the proportion drops of rapidly though. The
> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> into your calculator. It comes out around 12.8%, so that many molecules
> behave like they have a temperature of 100°C.
> 
> PS: for physicists: I understand that 1.5k*373 is not the same as the
> energy needed to sublimate. This is just to get across the idea that a
> significant proportion of molecules have much higher energy than the mean.
> 
> All solids and liquids have something called a "vapor pressure", which
> is essentially the average amount of gas molecules existing near the
> surface of the solid or liquid. If this vapor pressure of that gas at
> the puddle surface is higher than the number of molecules (of that gas)
> existing in the ambient, it will diffuse into the ambient, and there is
> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
> 
> This is why puddles evaporate quicker on drier days, and slower on humid
> days. And if the temperature drops (vapor pressure depends on
> temperature) and ambient humidity rises, this can go the other
> direction, and you get dew.

[toc] | [prev] | [next] | [standalone]

#642438

On 7/20/2017 8:08 PM, Serg io wrote:
> Glad you asked Claudius, many are so confused like you are on this subject.
> 
> Even though 100°C is the actual temperature needed for water to boil,
> the nature of matter is such that even under that temperature, some
> molecules have enough kinetic energy to convert to gaseous form.
> Temperature is merely the average kinetic energy of a system, so some
> molecules are above that temperature and some are below at all times.
> Under 100°C, say at 80°C, some molecules would still have enough kinetic
> energy to convert to gaseous form.

> This is why water still evaporates over time, albeit very very slowly,
> from say, a puddle, on a cooler day. Increasing temperature just
> increases the rate of a favorable reaction that is naturally
> occurring/provides the conditions for it to spontaneously occur.
> Reactions favor the direction that increases the number of micro states
> available to the system (think in terms of wanting personal space - in
> general, gaseous form is more "comfortable" for a compound vs. being
> smooshed as a liquid or even more smooshed as a solid), some reactions
> just don't happen spontaneously without certain conditions or a
> catalyst, i.e. a specific temperature.
> 
> The "steam" you see is a mist* of the gaseous particles being condensed
> into tiny liquid particles suspended in the air, which is cooler than
> the system the gas just left.
> 
> For any substance, the energies of the molecules are spread out in a
> bell curve. So while the mean energy (what we call temperature) is 0°C
> or less, a proportion of molecules have energies that would correspond
> to 10°C or even 100°C. This is given by the formula:

> fraction of molecules with energy greater than ε = e-ε/kT where k is a
> constant, the Boltzmann constant, and T is the current temperature in
> Kelvin (Celsius + 273). e is 2.7182818.....
> 
> Since it's exponential, the proportion drops of rapidly though. The
> energy at a given temperature is 1.5kT, so try putting e-1.5*373/273
> into your calculator. It comes out around 12.8%, so that many molecules
> behave like they have a temperature of 100°C.
> 
> PS: for physicists: I understand that 1.5k*373 is not the same as the
> energy needed to sublimate. This is just to get across the idea that a
> significant proportion of molecules have much higher energy than the mean.
> 
> All solids and liquids have something called a "vapor pressure", which
> is essentially the average amount of gas molecules existing near the
> surface of the solid or liquid. If this vapor pressure of that gas at
> the puddle surface is higher than the number of molecules (of that gas)
> existing in the ambient, it will diffuse into the ambient, and there is
> a net transfer from the puddle to the atmosphere, hence the puddle shrinks.
> 
> This is why puddles evaporate quicker on drier days, and slower on humid
> days. And if the temperature drops (vapor pressure depends on
> temperature) and ambient humidity rises, this can go the other
> direction, and you get dew.
.

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