In the solid and liquid states of matter, volume is constant because the amount of matter does not change. In a gas however volume can change because of the amount of pressure and the temperature, which heats up the particles making them move around more and take up more space.
Plasma!
Assuming that pressure and the amount of matter are constant (meaning they do not change), volume will increase as temperature increases.
Liquids and solids are the states of matter that occupy a definite volume. Gases have neither a definite volume nor shape.
A given mass of gas can assume any shape and volume; a given mass of liquid can assume any shape but has a constant volume; and a given mass of a single solid has a fixed shape and volume.
There are two states of matter that has no definite volume or shape. They are a gas and plasma. Solid matter has a definite shape and volume.
Liquids. By assuming that temperature and pressure are constant so that volume does not change.
A liquid is a state of matter that has a definite volume but no definite shape. Liquids take the shape of their container but maintain a constant volume.
All states of matter - solid, liquid, and gas - have mass and volume. Mass refers to the amount of matter in an object, while volume is the amount of space it occupies. Plasma, the fourth state of matter, also has mass and volume.
Solid, liquid, and plasma states have definite volume.
The matter state with a definite volume but an indefinite shape is a liquid. Liquids take the shape of their container but maintain a constant volume.
If temperature remains constant and the volume of gas increases, the pressure will decrease. This is described by Boyle's Law, which states that pressure and volume are inversely proportional when temperature is constant.