A chlorine Cl atom is adsorbed on a small patch of surface (see sketch at right). This patch is known to contain 16 possible adsorption sites. The Cl atom has enough energy to move from site to site, so it could be on any one of them. Suppose a Br atom also becomes adsorbed onto the surface. Calculate the change in entropy. Round your answer to 2 significant digits, and be sure it has the correct unit symbol.