# FAQ: Which one of the following is always positive when a spontaneous process occurs?

## Which of these must be positive for a spontaneous process?

Hence, ΔStotal is positive for spontaneous reaction.

## What always increases in a spontaneous process?

The second law of thermodynamics states that the total entropy of the universe always increases for a spontaneous process. The second law of thermodynamics states that the total entropy of the universe always increases for a spontaneous process.

## What is true about a spontaneous process?

A spontaneous process is one that occurs on its own, without any energy input from the outside. For example, a ball will roll down an incline; water will flow downhill; ice will melt into water; radioisotopes will decay; and iron will rust.

## Which process is always spontaneous?

When ΔS > 0 and ΔH < 0, the process is always spontaneous as written. When ΔS < 0 and ΔH > 0, the process is never spontaneous, but the reverse process is always spontaneous. When ΔS > 0 and ΔH > 0, the process will be spontaneous at high temperatures and non-spontaneous at low temperatures.

You might be interested:  When you're connected to wifi does it use data?

## Which is true for spontaneous change?

Key Concepts and Summary. The second law of thermodynamics states that a spontaneous process increases the entropy of the universe, Suniv > 0. A negative value for ΔG indicates a spontaneous process; a positive ΔG indicates a nonspontaneous process; and a ΔG of zero indicates that the system is at equilibrium.

## Can a reaction be spontaneous in both directions?

All reactions occur spontaneously all the time, and their backward reactions too. If left alone for long enough, a system will eventually reach the point where the forward and backward reactions go at the same rate (and it’s not like they both stop altogether!) – that’s an equilibrium.

## What is meant by a spontaneous process?

A spontaneous process is capable of proceeding in a given direction without needing to be driven by an outside source of energy. An endergonic reaction (also called a nonspontaneous reaction) is a chemical reaction in which the standard change in free energy is positive and energy is absorbed.

## How do you know if a process is spontaneous without using calculations?

By considering these two factors, we come up with the Gibbs Free Energy equation to predict if a reaction will proceed spontaneously or not. If the Gibbs Free Energy is negative, then the reaction is spontaneous, and if it is positive, then it is nonspontaneous.

## Do all spontaneous processes increase entropy?

These results lead to a profound statement regarding the relation between entropy and spontaneity known as the second law of thermodynamics: all spontaneous changes cause an increase in the entropy of the universe. All spontaneous changes cause an increase in the entropy of the universe, i.e., ΔSuniv>0.

You might be interested:  Which imbalance results when systemic arterial blood co2 levels raise to abnormal values?

## What factors make a process spontaneous?

There are two factors that determine if a process will be spontaneous or not: Enthalpy- Reactions that give off energy tend to be spontaneous. Entropy- Entropy is a measure of the randomness or disorder in a system. Generally reactions that increase the randomness of the system are spontaneous.

## What is an example of a spontaneous reaction?

A roaring bonfire is an example of a spontaneous reaction, since it is exothermic (there is a decrease in the energy of the system as energy is released to the surroundings as heat). The products of a fire are composed partly of gases such as carbon dioxide and water vapor.

## Why is diffusion a spontaneous process?

Diffusion is a spontaneous process since one solute is independent of the concentration gradients of other solutes and because it involves a passive transport process, which implies that energy is not expended when substances diffuse down their concentration gradient.

## Which is not a spontaneous process?

Therefore, flow of heat from a cold body to a hot body is a non-spontaneous process as it requires external work as per Clausius.

## Are all irreversible processes spontaneous?

Irreversible processes cannot be undone by exactly reversing the change to the system. Spontaneous processes are irreversible.

## Are all spontaneous processes exothermic?

All spontaneous processes are not exothermic, because it is the Gibbs Free energy that determines spontaneity, not the enthalpy. This is a very exothermic process. But it also has a negative change in entropy, because a liquid is more orderly than a gas.