how does hot and cold air react?
601199
actually the hot air because of its lighter weight than cold air tends to go up and so cold air because of its more weight than hot air tends to come down and replace the hot air.
472455
Heat transfer can occur through convection (ex: In the winter, the wind makes you colder), conduction (ex: heating a pot of water on an electric stove), and radiation (ex: sunlight warming the earth).
453673
While it is true that hot air rises, it is also true that it will cool as it rises. This is called adiabatic cooling.\n\nAir pressure deminishes as you go to higher altitudes b/c there is less gravity. Less air pressure means air particles are more spread out. Hence the adiabatic cooling effect.\n\nThis is true in the troposphere, the atmospheric layer in which we live & where weather occurs.\n\nAs you go higher the reverse happens. In the stratosphere it gets warmer due to the ozone layer. In the mesosphere it gets colder again b/c you move away from the ozone layer. In the thermosphere it gets warmer again b/c of the bombardment of air particles by intense short wave solar radiation.
970477
When cold air hits your face or other exposed skin it can feel as if it is biting or nipping at you.\nNipply on the other hand is something quite different. :)
872856
It will eventually melt at 2572C, and it will boil at 2850C.\n\nHeat does not cause it to react, typically.
20445
These are physical changes.  The matter simple changes state, depending on tempature.  Also see evaporation.
273934
Hot air rises cold air descends.  Do it on a global scale and you get wind.
718599
As the water vapor cools along with the air, it begins to go into a liquid state and will collect on anything it can, usually dust particles in the air. From there, it depends on the amount of water and the air temperature whether you will get dew, rain or snow.
700445
It heats up the atmosphere in the day time and at night when there is no sun, heat rises from the ground creating disturbances in the atmoshpere, aka wind. The same applies to cold air sinking from the upper layers of the atmosphere to the ground.
73372
When the cold air touches the warm air, the humidity in the warm air will condense and fall as rain. The intensity of the rain will depend on how much humidity is in the air and the temperature difference between the cold and warm front.\n\nIf a 30°F cold front touches a 70°F warm front and there's a lot of moisture in the air, then it results in a massive thunderstorm.\n\nIf you see the doppler radar pictures on the news, you'll see that rain usually comes in bands. That band of rain is the leading edge of a cold front.
785888
It all depends on the exact composition of air. Air is a mixture of gasses, Nitrogen, Oxygen, Carbon Dioxide, Carbon monoxide and small amounts of various other gasses. Freezing occurs when the gaseous mixture turns from a liquid and then into a solid. Although it may theoretically be possible to solidify Air, it has not actually been reached.
629453
warm water dissolves ice faster than warm air because it can transfer and absorb heat faster than warm air of the same temperature
1063868
Heat air goes up in circles and flies just use air to help during their annoying activity. \n\nIn center of your room, air will invcrease temperature and being pushed by your walls temp. Then, in middle of it, you will have a small imperceptle "hurricane" of hot air. \n\nYou will hardly see it in ope spaces and excelent curiosity gift; \n\nlooks that you have a lot of free time.
1134140
Depends on the thermoconductive properties of a certain material. Copper for example will heat up or cool down very fast.
963889
A precipitate is a solid formed by a reaction. If you mix two chemicals in a test tube and a solid forms it is a precipitate.\n\nendothermic reactions absorb heat and will feel cold to the touch. Exothermic reactions give off heat and will feel warm or hot to the touch.
1136431
Should be simple.  Warm air rises because it is less dense than cool air.  Cool air rushes in to replace the rising warm air.\n\nPlug this simple formula into the complex real world of spinning globe, equitorial heat and polar regions & you get weather.
1159227
As a general rule, warm air rises and cool air sinks\nit expands and becomes lighter as the molecules of air move farther apart