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On Earth If we push a gas syringe very fast Inwards , work is done on the gas by W = PV which increases the Kinetic energy of molecules in it and since Temperature is Average Kinetic Energy thus Temperature increases However due to neighbouring atoms(around syringe) the kinetic energy is conducted outwards until Thermal Equilibrium is reached and this is how Boyles Law is maintained

But In space there is no air , so the Temperature would Increase Permanently

Hence Violating Boyles law ,

So my question is If my conclusion is correct, do gas Laws only work where there is AIR ?

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  • $\begingroup$ What is the violation of Boyle's Law? $\endgroup$
    – garyp
    Commented Sep 26, 2018 at 11:16
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    $\begingroup$ Putting aside that this isn't a violation of Boyle's Law, the gas in the syringe will radiate heat until it is in equilibrium with its surroundings. $\endgroup$
    – probably_someone
    Commented Sep 26, 2018 at 11:20
  • $\begingroup$ but thats the problem , there is no surrounding , should'nt two bodies be touching each other to achieve thermal equilibrium , a syring floating in space with with nearest planet miles apart , how can thermal equilibrium be achieved? $\endgroup$
    – Rix Vii
    Commented Sep 26, 2018 at 11:28
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    $\begingroup$ @RixVii The syringe (and everything else) is surrounded by a bath of radiation from the stars and planets around it and from the cosmic microwave background, among other sources. It comes into equilibrium with this bath of radiation. If it is hotter than the temperature of this radiation bath, then it will cool down. If it is colder than the surrounding radiation, then it will be warmed up. Far away from all sources of radiation except the cosmic microwave background (CMB), the object will cool to 2.7 Kelvin, the current temperature of the CMB. $\endgroup$
    – probably_someone
    Commented Sep 26, 2018 at 12:12
  • $\begingroup$ Radiation does not require physical contact. $\endgroup$
    – Solomon Slow
    Commented Sep 26, 2018 at 12:54

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Boyle's law states that for an isothermal process suffered by an (ideal) gas the pressure is inverse proportional to the volume (or PV=constant). A violation of Boyle's law means that you have an isothermal process in a gas and the pressure and volume have a different relationship than PV=constant.
If you have a non-isothermal process, there is no violation of Boyle's law, no matter what kind of relationship you have. Actually if the process is not isothermal, Boyle's law has nothing to do with it.

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Boyle's law is just a special case of the ideal gas equation, for an isothermal change. But you are putting too much emphasis on air and surroundings. This just means: Boyle's law holds, if the change is isothermal - usually that means you have some type of heat exchange that keeps the temperature constant when you are changin volume - it could be heat condution with outside gas, or a hot piston, or water bath, or kept constant with electric heater, or by exchange of thermal radiation through vacuum. It doesn't matter.

In thermodynamics, your "system" is always the only thing you care about. It's exchanging work and heat with surroundings, but the laws hold for the system regardless of the nature of environment and howe work and heat are passed in and out. There is nothing special about a piston in space. It's the same as just having an insulated piston. If we ignore other means of heat exchange, the change will not be isothermal, but adiabatic (if it's done reversibly). So Boyle's law is useless. You need the whole ideal gas equation and the details of the adiabatic process (the ratio of specific heats). So the result is increase in temperature, just like you would expect in any adiabatic change. It happens in your car's pistons, too.

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This will happen only if the container in which gas is present conducts 0 heat. This means that their is no exchange of heat from inside to outside. This will also happen on earth if we use that type of container and it is not the violation of boyle's law

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