What is the difference between endothermic reactions and exothermic reactions? (Please describe both types of chemical reactions.)

What are the similarities of physical and chemical change ?

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

How does the value of the equilibrium constant show that a reaction reaches equilibrium very quickly? (a) the equilibrium constant is large. (b) the equilibrium constant is small. (c) the equilibrium constant is zero. (d) the value of the equilibrium constant does not show how quickly a reaction comes to equilibrium.