Cuales son las reservas de petróleo en argentina?

Which of these conditions most likely produces an unstable isotope?

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.

Suppose that some of the compound spilled out of the crucible after it was heated. would that cause the percent by mass of water in the compound determined by the experiment to be too low, too high, or unchanged? briefly explain your answer.