Answer:
The differemt isotopes that differ in atomic mass
Explanation:
This problem is providing the mass, energy, initial temperature and specific heat of a sample of copper that is required to calculate the final temperature.
Thus, we recall the general heat equation:

Which has to be solved for the final temperature,
as follows:

Finally, we plug in the numbers to obtain:

However, this result is not given in the choices.
Learn more:
Answer:
The hydrogen molecules combine with the oxygen molecules, 2 hydrogen molecules, and 1 oxygen molecules is the amount needed to make one water atom or molecule, whatever you want to call it.