Answer: to only change one factor in an experiment or test
Answer:
low melting point
Ionic compounds have high melting and boiling points. This is because a considerable amount of energy is required to break the strong inter-ionic attraction
Explanation:
In an extremely simplified explanation,
What happens is that the steam (heat) that is generated by the burning of coal is used to rotate the motor of the steam engine.
I am pretty sure this is uranium. it has 140 neutrons.