This warming is in addition to carbon dioxide's better-known effect as a heat-trapping greenhouse gas. For scientists trying to predict global climate change in the coming century, the study underscores the importance of including plants in their climate models.
It is a physical change. All phase changes are physical, not chemical. The chemical composition of water does not change when it changes from a liquid to a gas, or for that ma â¦ tter, to a solid.
Steam and liquid water are two different forms of the same chemical substance, water. A chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e., without breaking chemical bonds. Chemical substances can be chemical elements, chemical compounds, ions or alloys.