Radioactivity Beta Decay

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What is Radioactivity?

Radioactivity comes under a dangerous phenomenon but is quite useful. It is the phenomenon that opened a door into the world of sub atoms and influenced the beginning of the nuclear revolution. 

Radioactive atoms possess a certain amount of energy and produce electromagnetic waves spontaneously. These emissions are named as radiation. On our earth, many radioactive materials are available naturally. These materials keep our planet warm. Radioactive materials produced cosmic rays continuously into the atmosphere. Nuclear reactors and particle accelerators utilize nuclear materials to produce radioactive material.

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The rate of radioactive element decays can be expressed as a half-life, which means the total time required for one-half the given quantity of isotope.


Radioactivity Beta Decay

Radioactive beta decay can be defined as the property of several elements available naturally along with isotopes produced artificial isotopes of the elements. 

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Radioactive beta decay occurs in the presence of many protons or many neutrons inside the nucleus. One of protons or neutrons can be transformed into a different form. 

The conservation of electric charge is required in this reaction. If a neutral neutron which transforms into proton electrically, another electrically negative particle will be produced. Here, we can depict that an electron can also be generated.

Three primary ways to differentiate this phenomenon are proton decay, neutron decay, and electron decay. Protons can be charged straight to form neutrons and vice-versa by using these three methods.

The atomic number is continuously changing in every single decay so that some different elements, such as parent atoms and daughter atoms, are formed.

This process is a weak interaction decay process. The beta decay is generally of two types. One is beta minus (β-), and the other one is beta plus (β+).


Beta Particles

Beta emitters are harmful to our bodies. A large amount of radiation of beta particles may cause skin burn and erosion. If they enter the body, they will cause some severe health issues. 

These beta particles are generally in the form of electrons or positrons (which are electrons with a positive electric charge).

The emission of the charged particles that flow from the nucleus of a radioactive element during the radioactive decay procedure or disintegration has a mass equal to 1/1837 as compared to the proton. The mass of the beta particle is half of one-thousandth of the mass of a proton. 

These particles carry either a single positive (positron) or negative (electron) charge. These particles can achieve relativistic speed, which is compared to the speed of light. It is possible because they have a small mass and can release high energy.

They lose energy through rapid interaction with matter, so they are lighter in mass. Though they move through air or other materials, their path becomes desultory.

Rather than the alpha particles, beta particles are much less ionized. They do less damage to a given quantity of energy deposition generally. They range from tens of centimeters in the air, which is energy-dependent; however, in the case of materials, it is a few.

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A beta decay process consists of carbon-14. It is used in radioactive dating techniques. The reaction of nitrogen-14 and electron is written below:

614C → 714N + -10e

Usually, the beta emission is denoted by the Greek letter. It is necessary to memorize the whole phenomenon to understand nuclear calculations with this Greek letter without any further notation.


Beta Minus Decay

In this type of decay, a neutron which is present inside the atom’s nucleus converts into a proton in beta minus decay. The electron and antineutron travel from the nucleus, which now has more than one proton before it started. 

Though an atom summons a proton at the time of beta-minus decay, it alters from one element to another. We can take an example as, after the ongoing beta-minus decay, an atom of carbon, which possesses 6 protons, will become an atom of nitrogen with 7 protons.

In this decay, a neutron is converted to yield a proton, making an increment in the atomic number of the atom. Here, a neutron is neutral, but the proton possesses a positive charge.

To make a balance in the conservation of charge, the nucleus produces an electron and an antineutrino in this process. Antineutrino is the antimatter. It is the counterpart of neutrinos. Both of these have less mass and are neutral particles.

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In beta minus decay, the change in atomic configuration is;

ZAX → Z + 1AY + e\[^{-}\] + v\[^{-}\]N = p + e\[^{-}\] + v\[^{-}\]

The decay of 14C and 14N is the best example of beta minus decay. It usually establishes the neutron-rich nuclei.


Beta Plus Decay

Here, a proton turns into a neutron; a positron and a neutrino inside an atom’s nucleus. Positron and neutrino travel from the nucleus which has less proton than before. Due to the loss of a proton during beta plus decayit changes to one element from another. Also, conservation of charge takes place. The beta plus decay conservation law also earns a positron and neutrino.

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ZAX → Z - 1AY + e\[^{+}\] + vN = p + e\[^{+}\] + v


Beta Emission

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Beta-decay or β decay represents the disintegration of a nucleus to become a daughter through beta particle emission.

The nucleus will lose an electron or positron when a nucleus emits a beta particle. Here, the mass of the daughter nucleus remains constant, and a different element is formed.

Beta particles possess high-energy, high-speed electrons emitted by certain radioactive nuclei like potassium-40. The range of penetration of beta particles is greater than the alpha particles. It still lacks the strength to beat gamma rays. The beta particles emitted are in the form of ionizing radiation, also called beta rays or beta emission.

FAQ (Frequently Asked Questions)

1. What is the Charge on the Beta Particle?

Ans: Beta particles possess a charge of -1. The mass of a beta particle is around 1/2000th of a proton. This implies that beta particles are the equivalent of an electron.

2. What are the Alpha and Beta Particles?

Ans: Ionizing radiation is categorized into three groups, such as alpha particles, beta particles, and gamma-ray. 

  • Alpha particles are not as dangerous as compared to others when it comes to external exposure. Each particle carries a pair of neutrons and a pair of protons.

  • Beta particles are generally electrons, which move very quickly with a lot of energy.

3. Mention Two Examples of Beta Decay?

Ans: There are two types of beta decay, such as beta plus and beta minus/.

Beta plus decay example:

1122Na → 1022Ne + e⁺ + v

Beta Minus decay example:

1532P → 1615S + e⁻ + v⁻

4. What are the Properties of Beta Particles?

Ans: A beta particle that is negatively charged is equivalent to an electron. 

  • A beta particle that is positively charged is called a positron. 

  • They move through air or other materials, and their path becomes desultory.