What is a major disadvantage of wood harvesting

What is the relation between concentration of reactants and the rate of chemical reaction?

Which class of molecules functions as chemical signals? hormones water carbohydrates proteins

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.