Sent to CCL by: Pedro Silva [pedros%x%ufp.edu.pt] Please use the Arrhenius or Eyring equations for answer to that question. CCL is not meant to solve undergrad homework problems. Pedro S. -- Pedro J. Silva Associate Professor Universidade Fernando Pessoa Porto - Portugal http://homepage.ufp.pt/pedros/science/science.htm http://biochemicalmatters.blogspot.com