What does air pressure do to boiling point?
471496
Increasing air pressure increases the boiling point of a liquid. The boiling point is the temperature at which the saturated vapour of a liquid is equal to the external (atmospheric) pressure. Since saturated vapour pressure increases as temperature increases then the boiling point will also increase if the external pressure increases and vice versa.
981813
The boiling point depends on the intermolecular forces.\nThe stronger the intremolecular forces, the more energy you need to break them and thus the higher the boiling point will be.\n\nPolar molecules attract each other through dipole-dipole forces. The higher the polarity, the more strong these forces will be (because you will have stronger dipoles)\nNon-polar molecules attract each other through dispersion forces which are much weaker than the dipole-dipole forces.\n\nTherefore polar molecules will have higher boiling points and as polarity increases the boiling point also increases.
968042
Boiling is vapour pressure phenomenon. A liquid always exerts a pressure in the space just above it due to evaporation of its surface molecule which is called vapor pressure of that particular liquid and as temperature is raised the vapour pressure goes on increasing. When vapor pressure of the liquid exceeds atmospheric pressure liquid starts to boil.\nin case of a mixture, the solute molecules bind the molecules of the solvent and thus there are fewer surface molecule available to evaporate from the liquid surface. Due to which vapour pressure exerted by a mixture is always less than vapor pressure of pure solvent. To make vapor pressure of mixture to reach the atmospheric pressure level its temperature should be raised more than temperature of solvent alone. Thats why a mixutre has a boiling point elevation.
820723
Atmospheric pressure is the pressure at any point in the Earth's atmosphere.\n\nIn most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point. Low pressure areas have less atmospheric mass above their location, whereas high pressure areas have more atmospheric mass above their location. Similarly, as elevation increases there is less overlying atmospheric mass, so that pressure decreases with increasing elevation. A column of air 1 square inch in cross section, measured from sea level to the top of the atmosphere, would weigh approximately 14.7 lb. A 1 m² column of air would weigh about 100 kilonewtons.\n\nStandard atmosphere (symbol: atm) is a unit of pressure and is defined as being precisely equal to 101,325 Pa. This value is intended to represent the mean sea level pressure at the latitude of Paris, France, and as a practical matter, approximates the mean sea level pressure for many of the industrialized nations (those with latitudes similar to Paris). One standard atmosphere is standard pressure used for pneumatic fluid power (ISO R554), and in the aerospace (ISO 2533) and petroleum (ISO 5024) industries.\n\nIn 1982, the International Union of Pure and Applied Chemistry (IUPAC) recommended that for the purposes of specifying the physical properties of substances, “the standard pressure” should be defined as precisely 100 kPa (≈750.062 torr) rather than the 101.325 kPa value of “one standard atmosphere”.[1] This value is used as the standard pressure for the compressor and the pneumatic tool industries (ISO 2787).[2] (see also Standard temperature and pressure)\n\nIn the United States, compressed air flow is often measured in "standard cubic feet" per unit of time, where the "standard" means the equivalent quantity of air at standard temperature and pressure. However, this standard atmosphere is defined slightly differently: temperature = 68 °F (20 °C), air density = 0.075 lb/ft³ (1.20 kg/m³), altitude = sea level, and relative humidity = 0%. In the air conditioning industry, the standard is often temperature = 32 °F (0 °C) instead. For natural gas, the petroleum industry uses a standard temperature of 60 °F (15.6 °C).\n\nAtmospheric pressure is often measured with a mercury barometer, and a height of approximately 760 mm (30 inches) of mercury is often used to teach, make visible, and illustrate (and measure) atmospheric pressure. However, since mercury is not a substance that humans commonly come in contact with, water often provides a more intuitive way to conceptualize the amount of pressure in one atmosphere.\n\nOne atmosphere (101.325 kPa or 14.7 lbf/in²) is the amount of pressure that can lift water approximately 10.3 m (33.9 feet). Thus, a diver at a depth 10.3 meters under water in a fresh-water lake experiences a pressure of about 2 atmospheres (1 atm for the air and 1 atm for the water).\n\nIn terms of city water pressure, one atmosphere is approximately one-half to one-fifth the pressure of typical city water mains (i.e., water pressure is around 2 to 5 atmospheres).\n\nThe most common type of barometer used in homes is the aneroid barometer (Figure 3). Inside this instrument is a small, flexible metal capsule called an aneroid cell. In the construction of the device, a vacuum is created inside the capsule so that small changes in outside air pressure cause the capsule to expand or contract. The size of the aneroid cell is then calibrated and any change in its volume is transmitted by springs and levers to an indicating arm that points to the corresponding atmospheric pressure.
82527
This is not chemistry, but physics. I presume you are boiling water in a can, then sealing it and cooling it. There is then less pressure inside the can, since the water takes up less space than the water vapor. There is now more pressure outside the can than inside the can. You have unbalanced forces, and the can is unable to resist the pressure.\n\nThis can of course get far more complicated, and we can discuss the ductility of the can, and continuum mechanics of the can, and its chemistry, but I do not think you want anything that advanced. If you do, let me know.
228883
One of the things which effects the boiling points of substances is the intermolecular forces of attraction between the particles....the higher thr attractive forces, the higher the boiling point.\n\nWhich molecule has the higher attractive forces, Methane (Ch4) or Ammonia (NH3)?\n\nSince Methane is a small, nonpolar, hydrocarbon, the only attractive force its molecules experience is london forces (AKA induced dipoles).\nAmmonia on the other hand not only experiences london forces, but also experiences one of the most attractive forces...Hydrogen bonding.  The Hydrogens on the ammonia molecule are held in a polar bond with the Nitrogen making them form a partial positive charge and the Nitrogen forms a partial negative charge.  When the partial + Hydrogens from other NH3 molecules get near the parial - Nitrogens, they are attrcted to eachother which raises the boiling point of the substance.\nFor this reason, Ammonia gas will have a higher boiling point than methane.  This is confirmed by looking at the actual boiling points for each gas.\n\nBOILING POINTS:\nAmmonia: -33.5 degrees C\nMethane: -161.6 degrees C
786932
Boiling point is the temperature at which the vapor pressure of a liquid is equal to the atmospheric pressure.  Raising the temperature of a liquid increases the vapor pressure.  The higher the vapor pressure of a liquid already is, the lower the temperature required for it to boil.  Oxygen has a lower boiling point than hydrogen because it has a higher vapor pressure.  The reason for this is because there are less intermolecular forces holding oxygen together than there are intermolecular forces holding together hydrogen chloride.  In oxygen, there are weak London forces and nonpolar-covalent bonds.  In hydrogen chloride, there are London forces AND a polar-covalent bond.
837121
Hmmm.. The one affecting the boiling point is the intermolecular force..\nAs you can see, most of the compound here is polar. \n\nTherefore all you have to do is if the compound is consisted only of 2 elements (Group 17), you'll have to calculate the electronegativity difference. The more difference between them, the boiling will increase as well.\n\nIf there is more than 2 atoms in a molecule, you'll have to see the dipole moment magnitude (a.k.a polarity). The higher the magnitude, the higher the boiling point will be.\n\n\npeace\nvixklen
48785
Boiling Point: 444.6 °C (717.75 K, 832.28 °F)
22783
The bubbles are not "air" as most of the other answers claim; they are gaseous water, otherwise known as steam.  reverie's assertion about water pressure is also incorrect.  In a pot, the bubbles primarily form at the bottom of the pan because that's the hottest part of the pan and water.  The water there gets above the boiling point (212 F) and changes to steam.  At first, surface tension keeps the bubble stuck to the pan. But when enough steam is generated to make the bubble large enough, the bouancy of the bubble forces it to rise to the surface.
48898
when a liquid boils, it literally turns into a gas (steam).  As the water at the top of the pot evaporates, the gas can go straight into the air. But when it evaporates (boils) at the bottom of the pot, it forms bubbles that have to float up to the top
585025
I don't know that you can, different solvents react differently to pressure, so I don't think it's a one eqaution fits all kind of process.  That's why they all have different graphs for phase vs temperature/pressure.  I'm sorry.\nSounds like you have a pretty high boiling point though, the things I've taken off that had to be real high temp were water, toluene, and pyridine.  Could it be one of them?  They smell pretty different, so you'd know which.  \nThat's an interesting question though, I've never stripped a solvent that I didn't know what it was.
300798
Actually, when u lower the pressure in a chamber of say a liquid..\nIt has to maintaing the Law Of Conservation Of Mass, so the liquid particles evapourate and becomes gas to compensate for the loss..\nthats why you can boil water below 100 deg on the ALPS and thats how they make liq nitrogen..\nNow i dont know whether you are asking in an adiabatic process or not..\nIn an adiabatic process, there is not change in the temperature, the phase change of the particles compensates for the change in pressure...\nBut if its not adiabatic, then basically what u are trying to is crunch many particles into smaller volume or pluck out peices of mass into larger volume..\nIn that case, bonds are created or destroyed. When bonds are created energy is taken in, so temperature goes down...\nWhen bonds are destroyed, energy is released so the temperature increases...\nSo u can synchronize with the absorption and emission rates too.. Its basically exothermic or endothermic depending on pressure...
316108
It depends on the purity of the water and the pressure of the system.  Pure water in normal atmospheric pressure boils at 212 F.
105979
the boiling point of water at sea level is 212 deg F. the boiling point of water in the mountains is different because the column of air is not as "tall" as it is at sea level. the boling point is when the vapor pressure of a heated liquid exceeds the atmospheric pressure. sea level has a certain atmospheric pressure and thus a certain boiling point for water. at high altitudes the pressure is less and below sea level the pressure is greater.
299546
water "boils" when the Kinetic energy (energy of motion and heat) cause the molecules of water to expand or separate far enough away that it changes from a liquid to a gas. The greater the force keeping the molecules together, the more energy it needs. On Earth, the force is air pressure. At sea level where the pressure is greatest, water boils at about 100 degrees Celsius. Up in the mountains at 7000 feet it would boil at 80 -90 degrees or even less. In space even the smallest amount of energy would cause it to "boil".\nIt takes one calorie to raise one gram of water one degree Celsius. If you trap the water in a container, you can get the heat of the water much higher than the boiling point. But it could explode if the container is too weak to handle the pressure. So don't try it.
601632
Water boiling has to do with air pressure.\n\nThe higher your elevation, the less pressure exerted on the water, so it can boil at a lower temperature.\n\nThe closer to sea level you get, the more air pressure there is, so it requires more energy to boil.  (Going lower then sea level will still increase the boiling temperature).\n\nIt's also important to note, that when water is boiling, it keeps a constant temperature.  So if you look at this graph of time vs average temperature....\n\n|.........../..\n|........../..\n|....------.... <---  Boiling Temperature\n|../...........\n|./............\n\nYou see that when the boiling occurs, the temperature does not increase.  Only when all the water is evaporated does the temperature increase.  This ALSO works for ice in water.  The water will remain at 0 degrees celcius till all the ice is melted.\n\nHope this helps you understand melting/boiling points.