Solid, liquid and gas are the three main states of matter. When a substance changes state, this is a physical change because no new substances are produced and the change is reversible.

Institute of Metabolic Science Cambridge Biomedical Campus Cambridge CB2 0QQ UK; kirsten.corder{at}mrc-epid.cam.ac.uk Objective To systematically review and meta-analyse how physical activity (PA) ...

It does not matter if a substance melts, freezes, boils, evaporates, condenses or sublimates - the mass does not change. These changes in state are called physical changes because the process can ...

The physical properties of seawater include ... Density in particular is an important property in ocean science because small spatial changes in density result in spatial variations in pressure ...