A soft keyboard (sometimes called an onscreen keyboard or software keyboard) is a system that replaces the hardware keyboard on a computing device with an on-screen image map.
An ideal gas is defined as one in which all collisions between atoms or molecules are perfectly eleastic and in which there are no intermolecular attractive forces. One can visualize it as a collection of perfectly hard spheres which collide but which otherwise do not interact with each other.
Ideal Gas Definition. An ideal gas is a gas whose pressure P, volume V, and temperature T are related by the ideal gas law. PV = nRT, where n is the number of moles of the gas and R is the ideal gas constant. Ideal gases are defined as having molecules with negligible size with an average molar kinetic energy dependent only on temperature. At low temperature, most gases behave enough like ideal gases that the ideal gas law can be applied to them.