When air is heated it either increases in volume, increases in pressure or both, depending on the conditions. Air is composed of several different gases, most notably nitrogen, oxygen and carbon dioxide, but the particular gas involved does not matter. All gases behave identically with an identical increase in temperature, as long as the other conditions are also identical.Continue Reading
Whether air expands or increases in pressure depends on whether it is restricted in any way from expanding. Expanding air also decreases in density. A sealed container of air cannot increase in volume when heated, so it only increases in pressure. Theoretically, in an unconstrained situation air only expands when heated, but in reality, since even surrounding air masses provide some resistance, an increase in temperature always creates at least a slight increase in pressure. A more significant example of both volume and pressure increasing would be a rubber balloon. Heating air in a balloon increases both pressure and volume, since, while the balloon is elastic and does expand, it also provides some resistance to that expansion.
The fundamental equation for exactly how a gas or mixture of gases behaves when heated is PV = nRT, where P = pressure, V = volume, n = the number of moles of gas molecules, R is the ideal gas constant and T = temperature.Learn more about Thermodynamics
When ice or any other solid melts, its potential energy increases. Indeed, this is the only increase in energy, since the thermal kinetic energy, or temperature, does not increase while melting. Potential energy is the latent energy that could be released by the water, and this increases because the water will release heat energy if it is frozen solid again.Full Answer >
As temperature increases, the density of liquids and gases decreases; as temperature decreases, the density increases. Density is the amount of mass per unit of volume.Full Answer >
Isothermal expansion is an increase in the volume of a quantity of gas while the temperature stays the same. A constant temperature means that the volume of a gas is entirely dependent on pressure, which decreases as the size of the container increases.Full Answer >
An isochoric process is a process in thermodynamics where the performance of work depends on the volume. The volume of a closed system undergoing an isovolumetric process remains constant during the process. In this case, the system does not work because the volume is constant.Full Answer >