Suppose you mix 20kg of oxygen is used to burn 20kg of wood. Energy is given off as heat and light. If all the ashes and gases are collected , how would the mass compare with that of the orginal substance? Explain your answer.
Isn't there a law some where called the law of conservation of energy; energy may not be created nor destroyed. So if you could mix 20 kg oxygen and 20 kg wood (40 kg total) and convert it to its products, what does that law tell you.
