Question

The reactants in a chemical reaction contain 900 J of chemical energy. The products of the reaction contain 9000 J of chemical energy. Which statement best describes this chemical reaction? The reaction absorbs 9000 J of energy from the surroundings as it proceeds. The reaction releases 9000 J of energy to the surroundings as it proceeds. The reaction absorbs 8100 J of energy from the surroundings as it proceeds. The reaction releases 8100 J of energy to the surroundings as it proceeds. The answer is C

Answer 1

The reaction absorbs 8100 J of energy from the surroundings as it proceeds.

Answer 2

For the reaction to take place the energy of the reactants must reach to the energy level of the products:
we have 900 J in the reactants and 9000 J for the products so the reactants need 8100 J to reach to the value of energy of products (900 + 8100 = 9000)
So the correct answer is C. The reaction absorbs 8100 J of energy from the surroundings as it proceeds.