How is mechanical energy related to potential energy and to kinetic energy

 An object's ability to do work is measured by its mechanical energy, or the sum the object's kinetic energy and potential energy. Mechanical energy is due to the position or movement of an object. The formula for mechanical energy is mechanical energy = kinetic energy + potential energy.

Explanation:

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.