A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy without being used up in the reaction. After the reaction occurs, a catalyst returns to its original state and so catalysts can be used over and over again.
The total number of protons and neutrons in a nucleus
Answer:
By presenting the results in a poster session.
Explanation:
Several scientists from different countries are asked to examine the results of an experiment before a journal will print it.
Heat flows from high temperature to low temperature
