4) How many moles of O2 are produced with 42.0 moles of H2O?

1.2353 mol

Explanation:

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

i think it is true since you can test the answer and can use observations to complete it.