At room temperature the substance is at a temperature between melting point and boiling point. So it Will be a liquid. So the phase of a substance liquid gas or solid depends on their melting points, boiling points, room temperature and pressure.
Gases have covalent bonds and metals have ionic bonds.. Not sure about water Edit: I looked it up, water has polar covalent bonds. Polar bonds are when electrons are shared unequally by the elements involved in the bond, so Hydrogen and Oxygen.
Solids never change their shape as opposed to gases and liquids. This is because their molecules are tightly packed together. Since all solids have a definite shape, it's volume will also be definite.
