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A person eats 250 g of bread that contains 1000 kcal of food energy (chemical energy). [1 kcal = 4190 J]. During the chemical reaction, the bread combines with 02 resulting in the production of H20, C02 and heat. A chemist would say that the mass of the products equals the mass of the reactants. However, this is not exactly the case. The mass of the products is slightly less than the mass of the reactants. What is the net loss of mass after 250 g of bread have been consumed