“What happens to the volume of objects upon a temperature change?”
Let’s think about something. All objects are composed of vibrating atoms. And when an object is heated, those vibrations become more powerful, and the lengths of their vibration increase. So, what does this imply on the macroscopic scale? Well, if an object’s volume is determined by the volume of space that this volume of atoms takes up, and this volume increases, then the volume object should increase as well, therefore, heating causes (most but not all) objects to expand. Scientists and Engineers have named this phenomena thermal expansion. Thermal expansion is a very omnipresent physical phenomena, and can have dire implications for works of engineering if not taken care of.