Questions from Properties of gases

Senarita asked:

“we know that temperature has a properties to make some thing bigger in volume.we say that gas has no particular volume or shape.where we place a gas it takes the shape of that container.my question is- a gas of mass 'm' has a particular number of atoms or molecules.if the gas is not getting any temperature then how it is occupying all the volume of a bigger container.i mean how the inner space of two atoms or two molecules of that particular gas is increasing when i am transferring it to a bigger container.(say,every condition is constant.nothing is changed.)please answer me.”

can you give me some name of sites where i can get explanations on hydrostatics or the topics of physics.i am now in class 11

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