Question

What gas law applies to space?

Answer 1

According to an ideal gas hypothesis, all gas molecules are identical and have negligible volume and they obey all gas laws. Also, they do not lose any energy during collision (perfectly elastic).In space, astronauts have to be very careful about the consumption of resources during their journey, since the resource is very limited and resupply is very difficult. Hence calculation and prediction are very important during space flight.

Complete answer:
Boyle’s law: It was first proposed by Robert Boyle based on research of Richard Towneley & Henry Power. It states that for an ideal gas, the pressure is inversely proportional to the volume at a constant temperature.
$P \propto \dfrac{1}{V} \Rightarrow PV = constant$

Avogadro’s law: It states that at constant pressure and temperature, the number of molecules in a given volume will remain constant.
$V \propto n \Rightarrow \dfrac{V}{n} = constant$
As we know in space the amount of fuel and oxygen is taken from the earth, hence it is very important to calculate the accurate amount of resources needed during their journey.
Avogadro's law and Boyle’s law are used to predict the amount of fuel and oxygen needed and can be filled safely in a spacecraft without risking astronauts’ life.

Additional information: The assumption for an ideal gas according to the kinetic theory of gases are:
-Each gas molecule occupies negligible volume as compared to gas itself.
-Ideal gas molecules neither exert force on each other nor on their surroundings.
-An ideal gas is in a constant state of random motion and always moves along a straight line.
-For an ideal gas, each collision is perfectly elastic, and total kinetic energy during such collisions is always constant.

Note: As we discussed, according to the assumption of ideal gas there is no force of attraction and repulsion between gas molecules. But in real life, we know that gas molecules exert the force of attraction and repulsion also have some volume. Because of this in real life at low temperature and pressure, we see gas won’t behave as we assumed according to the ideal gas equation.