<span>The liquid form of matter is usually more dense than its gas form. This is because liquid molecules are closer together compared to gas molecules. An exception, however, is water. Water's solid form or ice is less dense than its liquid form because of the orientation of hydrogen bonds that lowers its density.</span>
When elements are combined to form compounds, they undergo chemical change in which the properties of the composing elements are always different from the compounds formed after reaction. The change is not only applicable to the chemical properties of the elements but also the physical states of the substances. Answer then is B.
The matter of changes in volume is gas
