Why does nuclear decay occur and how is it random?

Nuclear decay occurs due to instability in an atom's nucleus and it is random due to quantum mechanics.

Nuclear decay, also known as radioactive decay, is a process that unstable atoms undergo to become more stable. Atoms are made up of protons, neutrons, and electrons. The protons and neutrons form the nucleus of the atom, while the electrons orbit around the nucleus. The stability of an atom's nucleus is determined by the balance between the protons and neutrons. If there is an imbalance, the nucleus becomes unstable and the atom will try to correct this by undergoing nuclear decay.

The process of nuclear decay involves the release of particles and energy from the unstable nucleus. This can happen in several ways, such as alpha decay (where an alpha particle, consisting of two protons and two neutrons, is emitted), beta decay (where a neutron is converted into a proton and an electron, and the electron is emitted), or gamma decay (where energy is released in the form of gamma rays).

The randomness of nuclear decay is a result of quantum mechanics, a branch of physics that deals with phenomena on a very small scale, such as atoms and subatomic particles. According to quantum mechanics, it is impossible to predict exactly when a specific atom will decay. Instead, we can only predict the probability that an atom will decay over a certain period of time. This probability is constant for a given atom, which means that nuclear decay is a random process.

For example, if we have a large number of atoms of a radioactive substance, we can predict how many will decay over a certain period of time, but we cannot predict which specific atoms will decay. This is similar to tossing a coin: we can predict that half the time we will get heads and half the time we will get tails, but we cannot predict the outcome of a specific toss.

In summary, nuclear decay is a process that occurs when an atom's nucleus is unstable and needs to correct its balance of protons and neutrons. The randomness of this process is a result of the principles of quantum mechanics.