Question

Is cellular respiration spontaneous or not? How can you tell?

Answer 1

Respiration is called the process by which the nutrients which we eat get converted into useful energy. As we usually know, the cell is called the structural & the functional unit of life and each of the cells requires the energy to perform its functions. Therefore, respiration which takes place at the smallest level of our body i.e cellular level is called cellular respiration. The process also ensures that each of the cells also performs its function in a perfectly designed manner.

Complete answer:
Cellular respiration is also called a process by which a set of metabolic reactions occurs inside the cells to convert the biochemical energy which is obtained from the food into a chemical compound which is called as the adenosine triphosphate (ATP). Metabolism generally refers to a set of chemical reactions which is carried out for maintaining the living state of the cells in an organism. Respiration is also a catabolic process, which usually breaks the large molecules into the smaller ones, releasing the energy into fuel cellular activities.
Spontaneous reactions also have a decrease in the enthalpy (total energy) and an increase in entropy (disorder).
This also comes with the law of physics which is things in nature, when left to themselves, it will then become more disordered and then it will also lose energy. This is also known as the Second Law of Thermodynamics. Spontaneous reactions are when a reaction happens naturally, in order to lose the energy from a system and then it becomes more disordered.
Entropy can usually also be described as the energy which is released by a system when something happens. The fact that respiration releases energy means that it also has a positive entropy. Because the products, carbon dioxide and the water have a lower energy than the reactants, which is primarily glucose, this means that it is an exothermic reaction and so it has a negative enthalpy. This also makes sense because respiration usually releases energy from the glucose.

Note: As you can see, respiration fits the requirements for the spontaneous reaction. It is positive entropy and negative enthalpy. Respiration is also spontaneous as it releases energy (negative enthalpy) and then it becomes more disordered (positive entropy).