Air pressure is caused by the density of gas molecules in the air.
true or false?

The correct answer would be true

True

Explanation: Pressure is defined as the force acting per unit area. The air pressure is due to the bombardment of the gas molecules against a surface.

Density is defined as the mass per unit volume of a substance. Thus, density of gas is defined as the mass of gas per unit volume.

If density of gas is higher, there are more number of molecules present and thus there will be greater bombardment and thus greater pressure.

their crystal patterns have been disrupted by stress

there are no atoms