So earlier in another lecture, we spoke about the relationship between temperature and reaction rate. And we said that as we increase our temperature, our reaction rate also increases because on average, more molecules will have enough kinetic energy to overcome the activation energy. Now, today we're going to look at something called catalysts. Now, catalysts are organic or inorganic molecules that also, like temperature, affect our rate of reaction. Now, let's look at the following hypothetical example in which reactants A plus B react to form a product AB. Now, let's suppose that our reaction is reversible, meaning it goes forward and backward.