A spontaneous process is one that occurs without the intervention of anybody else. A spontaneous process might go quickly or slowly. The driving force for a spontaneous process is a rise in the universe's entropy. Spontaneous processes are part of what makes up life as we know it, and they occur everywhere around us. Spontaneous events are difficult to prevent and impossible to predict.
Spontaneity can be good or bad. Good spon-teity means doing something without thinking about it first. This can be good or bad depending on what you do. Bad spon-teity means acting without considering the consequences of your actions. This can have serious negative effects on yourself and others. Humans are naturally curious beings who like to find out more about things. We ask questions, try things out, and make assumptions based on what we see and feel. All of this is natural and important for us to function in today's world. However, humans also need time to think quietly by themselves. This is where spon-taneity comes into play. It allows people to do things independently without being judged or criticized for how they act.
People drive forces of spontaneity in their lives every day. Some people are driven by curiosity while others drive it away by trying not to think too much. Either way, spontaneity is essential for humans to function properly.
A spontaneous process in chemistry is one that happens without the input of external energy. Because spontaneity is unrelated to kinetics or response rate, a spontaneous process might occur swiftly or slowly. Spontaneous reactions are important because they are common and can be very useful in preparing starting materials for more complex reactions.
The most common example of a spontaneous reaction is the combustion of gasoline, which is a chain reaction involving many molecules occurring at the same time. In fact, the word "combustion" comes from the Latin combustus, meaning "burned," because of the flames produced by this type of reaction.
Spontaneous reactions are also important in physics. For example, the radioactive decay of uranium occurs spontaneously, without the help of any other particles or forces. This phenomenon is responsible for the generation of energy within the Earth over time.
In chemistry, the term "spontaneous" was first used by Wilhelm Ostwald to describe an exothermic chemical reaction. An exothermic reaction produces more heat than it takes to run the reactor, so it must be accompanied by an endothermic reaction to keep the system at equilibrium. The endothermic reaction in this case is water vaporization into steam.
A spontaneous process is one that, once started, continues on its own without the input of energy. A non-spontaneous process needs a continual input of energy. For example, when you light a fire, some of the wood will always burn until it is gone. But if you keep lighting fires then soon all of the wood will be burned up. This is because burning material is constantly replaced by new growth which will be burned in its turn and so on forever.
Spontaneous processes are usually very efficient and do not waste any energy. For example, the wind blows trees down and their branches break off spreading their seeds over a large area. The seeds grow into small plants which again get blown over by the wind etc. Until one day there is no more forest land. This would be impossible for humans to do because we need lots of tools to cut trees down and make fires to cook our food. Also, most plants need water to survive and this is not easy to find either on land or in water. So overall, spontaneous processes are good for us because they help conserve energy like we saw earlier.
Spontaneous processes can also be dangerous. For example, if you stay in the same house for many years then eventually it will collapse around you.
There are two criteria that affect whether or not a process will be spontaneous: Enthalpy: Reactions that emit energy are usually spontaneous. Entropy is a measure of a system's unpredictability or chaos. In general, spontaneous reactions enhance the unpredictability of the system. Complexity: Spontaneous processes are often simple. The simplest chemical reaction is a homolysis reaction, which is simply a splitting reaction. Homolysis reactions are easy to predict because there are only a few possible products.
Spontaneous processes do not always lead to simple products. For example, when hydrogen gas is burned, it produces water vapor and heat. However, most other substances would be destroyed in this reaction! But even though burning hydrogen does not always result in water, it can still be considered spontaneous because the final state is more disordered (less organized) than the initial state. As another example, when carbon monoxide binds to iron(II), it forms carboxyhemoglobin. There is no way to tell from just looking at the mixture what compound will form - it could be any of hundreds of compounds. But even though carboxyhemoglobin is not one of the many possible products, it is still considered a product of a spontaneous reaction because there is no way to know how it will bind to the iron until it has time to react.
Spontaneous processes may also lead to complex products.
Entropy is a general measure of spontaneity. This indicates that if (dS) > 0 for any process, the process is spontaneous. The vast majority of chemical reactions take place under conditions of constant temperature and pressure. Under these conditions, they are called spontaneous. In fact, there are so many reactions that cannot happen under those conditions that they do not occur at all. For example, there is no reaction between hydrogen and oxygen at standard temperature and pressure. Spontaneous processes are responsible for the formation of molecules from atoms (e.g., gas bubbles, water vapor, ammonia), the formation of compounds (e.g., sugar, meat), the evolution of energy (e.g., fire, photosynthesis), and life itself. There are three main types of spontaneity: statistical, reactive, and integral.
Statistical spontaneity occurs when the number of possibilities in a large system goes up or down depending on how much information is available. For example, if we have a bag with 50 white balls and 50 black balls and we draw one ball at a time without looking at it, then the probability that this first ball will be white is half because there are only two possibilities: white or black. However, if we repeat this experiment many times, then the probability that we get the same result each time goes down to zero because there are an infinite number of ways we can pick out each single ball.