Let the floor dry thoroughly. Step 3: Use your favorite method to lightly abrade the top layer of finish: Sand around the perimeter of the room by hand with a 120-grit screen. For the middle of the floor you can use a pole sander with a 120-grit screen, or a floor buffer with a pad and a 150-grit screen. screen and recoat is the best-kept secret in the hardwood flooring world. But it shouldn't be, because it can save you money, labor and time over the life of your hardwood floor. Read on, and remember, the buffer is your friend.
There are six distinct changes of phase which happens to different substances at different temperatures. The six changes are: 1  Freezing: the substance changes from a liquid to a solid.  Melting: the substance changes back from the solid to the liquid.
For example, the freezing of water would be a physical change because it can be reversed, whereas the burning of wood is a chemical change - you can't 'unburn' it. A physical change is a change in which no new substance is formed; a chemical change results in the formation of one or more new substances.