Neutrons Last Updated : 25 Feb, 2024 Comments Improve Suggest changes Like Article Like Report Neutrons are fundamental subatomic particles of the atom. An atom is made up of electrons, protons and neutrons. James Chadwick, an English physicist, discovered the neutron in 1932. Neutrons are particles with no charge and higher mass. They are represented by n. They reside inside the nucleus of the atom and along with protons they are called nucleons. Let's learn about neutrons in detail in this article. What is Neutron?Neutrons are subatomic particles that are one of the primary constituents of atomic nuclei within Electrons and Protons. Neutron, neutral subatomic particle that is a constituent of every atomic nucleus except ordinary hydrogen. Neutrons and protons are together termed nucleons since they behave in a very similar manner within the nuclei of atoms. The number of nucleons is also called the Mass number. The mass of a nucleon may be roughly approximated to at least one mass unit (often abbreviated to a.m.u.). The branch of science that deals with the study of the properties of neutrons and also the interactions of those subatomic particles with different matter and nonparticulate radiation is named atomic physics. A neutron is present inside the nucleus of an atom, Hydrogen atom does not contain a nucleus. As protons and neutrons, both are present inside the nucleus, they are combinedly and known as nucleons. The image given below shows the electrons, protons and neutrons of an atom. Discovery of NeutronThe existence of neutrons was noted with the help of the Rutherford Nuclear Model of the Atom. there are a few points noted in the discovery of neutrons. (It also gives us remarkable information on the arrangement of the constituent particles) In this experiment where most of the alpha particle passes unreflected.some of them deviate through smaller angles and some with an angle greater than 180 degrees.Thus it indicated the presence of a particle in the middle part of the atom i.e nucleus; it marked the presence of a mass particle and the neutron was discovered later in 1932 by James Chadwick.The image given below shows the setup for the discovery of Neutrons. As electrons have negligible mass and this means the mass of an atom is only due to the proton only but it would create problems in the model thus it was indicated the presence of some neutral particle with a proton that has equal mass to that of a proton must be present in the atom. Rutherford realized that the atomic mass of different species cannot be determined unless there is the presence of another particle thus, Rutherford in 1920 stated that there is a kind of neutral particle with a mass equal to the mass proton present. James Chadwick, in 1932 during the study of the artificial transmutation of atoms, discovered a particle indicated by Rutherford in 1920. When a fast-moving alpha particle is bombarded with a thin foil of beryllium and beryllium changes into carbon and emits a neutral particle of the same mass as the proton. This new fundamental particle was named neutron because of its neutral nature and The particle was also found in many other reactions. Charge and Mass of NeutronA neutron has no electric charge linked with it. Neutrons are neutrally charged subatomic particles as a result.A neutron's mass is approximately 1.008 atomic mass units. The mass of a neutron is approximately 1.674 × 10-27 kg when measured in kilograms.Because neutrons do not have an electric charge, mass spectrometry cannot be used to estimate their mass directly.By subtracting the mass of a proton from the mass of a deuterium nucleus (deuterium is a hydrogen isotope with one proton, one electron, and one neutron in its atomic structure), the mass of the neutron may be computed. Because the mass of the electron is so little in comparison to the proton and neutron, the mass of the neutron may be estimated by subtracting the proton's mass from the mass of the deuterium atom.Applications of NeutronsVarious applications of Neutrons are, Neutrons are highly ionised and penetrating particles that can be employed in boron capture therapy and medical applications. However, when absorbed, they activate the substance and make it radioactive.It is significant in nuclear reactions (understanding of the neutron's behaviour, in particular, has aided in the creation of nuclear weapons and reactors).The neutron activation analysis (NAA) method is used to study a simple sample of materials in a nuclear reactor, and the neutron emitter is used to locate light nuclei in the environment.It is utilised in medical neutron tomography, but it has unfavorable side effects that leave the afflicted area radioactive, hence it is not frequently employed. The neutron lens was being developed at the time.It's utilised in boron capture treatment, which uses a tiny neutron beam to treat cancer. The energy delivered to malignant regions by neutron radiation is orders of magnitude larger than that delivered by gamma radiation.Uranium-235 and plutonium-239 are virtually always utilised in nuclear fission reactors due to nucleus absorption.Warm, hot, and cold neutron applications are employed in nuclear scattering facilities where radiation is utilised to condensate matter in X-ray studies.Properties of NeutronsVarious properties of Neutrons are, The magnetic moment of neutrons is not equal to zero, despite the fact that they are considered neutral particles. Despite the fact that electric fields have no effect on neutrons, magnetic fields have an influence on these subatomic particles. Neutrons have a lot of penetration, although not as much as cosmic rays. They haven't been able to ionise a gas yet. The approximate mass of an atom in a.m.u is equal to the entire sum of the neutron and proton present in an atom (atomic mass unit). Its mass is calculated by subtracting the proton's mass from the atomic mass.The magnetic field affects these subatomic particles, whereas an electric field has no influence on them. Its magnetic field is linked to the substructure of quarks and the charge's internal distribution.Neutron is made up of three quarks, which are the fundamental particles that give neutron its magnetic properties.The table below shows the important other characteristics related to Neutrons, SymbolnNatureNeutralRelative mass Equal to H atom Actual mass1.6 × 10-27 kgStability of NucleusThe nucleus of an atom contains neutrons and protons which are combinedly and called nucleons. The nucleus has positively charged particles and protons which tend to repel each other but they reside inside the nucleus due to strong nuclear forces. the stability of neutrons is explained by strong nuclear forces. A nucleus also has neutrons inside its nucleus and the ratio of protons and neutrons is close to 1:1 if the ratio changes the nucleus becomes unstable and radioactive decay occurs. Weak nuclear forces are responsible for this decay. Elements having the same number of protons but different numbers of neutrons are called isotopes. Elements with a higher atomic number are radioactive in nature. i.e. their nucleus has radioactive decay. Example: Hydrogen has three Isotopes and out of which two are radioactive. The image given below shows the isophote of hydrogen. Also, Check Structure of NucleusNuclear Binding EnergyAtomic StructureSolved Example on NeutronsExample 1: Calculate the number of neutrons in the sodium atom. Solution: Atomic number of sodium (Na) is 11 Mass number of sodium is 23 Thus, No. of neutrons = Mass Number − Atomic Number = 23-11 = 12 Example 2: What is the atomic mass of Nitrogen? Solution: Let the atomic mass of Nitrogen be a. Thus, No. of Neutrons = Mass Number − Atomic Number 7 = A - 7 A = 14 Hence, the Atomic Mass of nitrogen is 14. Comment More infoAdvertise with us Next Article Valency C chauhanishan82 Follow Improve Article Tags : School Learning Class 9 Chemistry Chemistry-Class-9 Atoms-and-Ions +1 More Similar Reads CBSE Class 9 Chemistry Notes Chemistry is a branch of science that studies the structure of substances and what happens to them in different conditions or when mixed with each other. The fundamental elements of Matter, Atoms, and Molecules are the main focus of Class 9 Chemistry Notes. These Chemistry notes will help not even t 5 min read Chapter 1: Matter in our SurroundingsMatter is Made of Tiny ParticlesIn our surroundings, we come across different shapes, sizes, heights, structures, and textures. According to scientists everything in this universe is made up of a material called Matter. 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As Concentration is a frequently used term in chemistry and other relevant fields, a 14 min read SuspensionsSuspension is a heterogeneous mixture of a fluid that contains solute particles that are considerably large for the process of sedimentation. Suspensions are considered to be heterogeneous in nature because they contain at least two different substances. The particles in a suspension are easily visi 6 min read ColloidsColloids or Colloidal Solution is a type of mixture in which insoluble components are suspended on a microscopic scale in some another component. Colloids are essential components in the daily lives of the common man, as we use or consume colloids and we even don't know. From Jellys to Mayonese to t 11 min read How will you distinguish a Colloid from a Solution?A colloid is a mixture in which one material is suspended throughout another substance and contains scattered insoluble particles. The whole mixture is referred to as a colloidal solution. A colloid has a dispersed phase (suspended particles) and a continuous phase, unlike a solution, which has only 7 min read Classification of ColloidsBefore we get into the specifics of how we classify colloids, it's important to first define what a colloid is. A colloid is a material made up of big molecules mixed with another substance in chemistry. This encompasses a wide range of items, many of which you may already have in your house, which 8 min read Tyndall EffectTyndall effect is the scattering of light by a colloid or an extremely tiny solution of particles. It is also known as the Tyndall phenomenon and is similar to Rayleigh scattering, in that the intensity of the scattered light is inversely proportional to the wavelength's fourth power, with blue ligh 6 min read Separation of MixturesSeparation of Mixtures or method of separation is the process of separating or extracting different components of a mixture using some physical methods. The type of mixture and variations in the chemical characteristics of the mixture's components determine the separation method to be used. Separati 14 min read How to separate a Mixture of Two Solids?As we look at our surroundings, we see many things with different shapes, sizes and textures. Everything in this universe is made up of material which scientists call matter. The air we breathe, the food we eat, stones, clouds, stars, plants and animals, even a small drop of water or a particle of s 8 min read Separation by a suitable solventMany of the substances we come into contact with mix. Two or more chemicals are combined together in these combinations. In other cases, such a blend may not be possible to employ in both households and businesses. For our purposes, we may just need one (or two) distinct elements of a combination. T 5 min read Separation of Mixtures using Sublimation and MagnetsSublimation is the separation technique where a substance makes a transition from the solid to the gas state directly. The substance does not undergo the liquid stage. Therefore, it is used to illustrate a solid-to-gas transition between the states of a substance. This process is endothermic in natu 11 min read How to Separate a Mixture of a Solid and a Liquid?In our daily life, we use different products. And, always keep in search of pure products as mostly also found written on the packaging of items. But scientifically the term pure is used for those matters which are made up of particles that have the same chemical nature or formation. Hence, the majo 10 min read Filtration: Definition, Process, Diagram and ExamplesFiltration is a method to separate the components of a mixture where the solvent part is liquid and the solute is an insoluble solid. Let's know more about Filtration Definition, Process, Application and examples in detail below. Filtration In simple words, Filtration is the process in which solid p 5 min read Water PurificationWater is carried through canals or lengthy pipelines in a water purification system, which contains various pollutants and suspended particles from rivers and lakes. River water is commonly used to supply cities with drinking and dining water. This water is unsafe for drinking or dining because it c 6 min read CentrifugationCentrifugation is a technique used to separate components of a mixture based on their size, shape, viscosity and density. It works by spinning the mixture at high speed in a machine called a centrifuge, which creates a force called centrifugal force. This force pushes denser components outward, away 12 min read Difference Between Homogeneous and Heterogeneous MixtureMixture is a combination of two or more substances that are not chemically bonded together. These substances can be elements, compounds, or both. There are two types of mixtures: Homogeneous and Heterogenous Mixture. In homogeneous mixture, components are uniformly distributed and not easily disting 4 min read Difference Between Compound and MixtureThe matter is divided into three main types Compounds, Mixtures, and Elements. Pure substances are compounds. Impure substances are Mixtures. The key difference between compounds and mixtures is that a compound is made up of molecules, each of which is composed of two or more different types of chem 7 min read Factors affecting SolubilityA solution is a liquid that is a homogeneous combination of one or more solutes and a solvent. A frequent example of a solution is sugar cubes added to a cup of tea or coffee. Solubility is the characteristic that allows sugar molecules to dissolve. As a result, the term solubility may be defined as 6 min read Separation by EvaporationEvaporation is the process of the separation of a solid substance that is dissolved in water. The application is based on the fact that solids do not vaporize easily, whereas liquids do. On performing evaporation, the solid substance is left behind as a residue. It is a vaporization technique where 7 min read CrystallizationCrystallization is a technique for purification of the substances. It is a technique that separates a solid from its solution. The process in which the solid dissolve in the liquid arranges itself in well-defined 3-D structures called the crystal is called crystallization. When any substance undergo 9 min read ChromatographyChromatography is the separation of mixtures by distribution between two or more immiscible phases. In chemical laboratories, where it is used for analysis, isolation, and purification, chromatography is the most used separation technique. It is also frequently used in the chemical process industry 15 min read DistillationDistillation is the method of separating mixtures, in which the conversion of a liquid into vapour is afterwards condensed back to liquid form. distillation method is used for the purification of metals. Distillation is preferable where both solid and liquid have to be extracted from the solution. A 9 min read Separation of Mixtures of Two or More LiquidsMost of the time, the substances we encounter are not in their purest form. They are essentially a chemical synthesis of two or more substances. Surprisingly, mixtures can take on a number of forms. As a result, many types of separation processes are used to separate a mixture of substances. When it 8 min read Fractional DistillationFractional Distillation is a technique used in the separation of miscible liquids. The process requires repeated distillations and condensations of the mixture. The separation of the mixture happens when the mixture is heated at a certain temperature where fractions of the mixture start to vaporize 7 min read Pure and Impure SubstancesSubstance is a matter which is associated with a set of definite properties and composition. Every pure compound and element is a substance. Substances are the materials composed of atoms and molecules. Every substance is recognized by a specific weight and volume. It cannot be segregated into other 4 min read What is an Element?Element in chemistry are substances that cannot be broken down into simpler substances by any chemical method by the application of heat or light. For instance, melting a piece of gold still remains the gold element. These substances are composed of a singular type of atoms i.e., they are monoatomic 12 min read Metals, Non-Metals and MetalloidsMatter is defined as any substance that has mass and occupies space by having a volume in classical physics and general chemistry. Daily objects that can be touched are ultimately made up of atoms, which are made up of interacting subatomic particles, and matter refers to atoms and everything made u 8 min read Properties of Metals and Non-MetalsMetals and Non-metals have different properties and reactivity with other elements. This difference between the physical and chemical properties of elements depends on their position in the periodic table. The physical properties of substances (or elements) include tendencies like conductivity, dens 7 min read Chapter 3: Atoms and MoleculesLaws of Chemical CombinationLaws of Chemical Combination are one of the most fundamental building blocks of the subject of chemistry. As in our surrounding different matter reacts with each other and form various kind of different substances. Laws of Chemical Combination are the collection of laws that explains how these subst 7 min read Law of Conservation of MassLaw of Conservation of Mass: The law of conservation of mass states that the mass can neither be created nor destroyed in a chemical reaction. This implies, in a closed system the mass of the elements involved initially in a chemical reaction is equal to the mass of the product obtained by the react 9 min read Verification of the Law of Conservation of Mass in a Chemical ReactionLaw of conservation of mass states that "The mass can neither be created nor destroyed in a chemical reaction" French chemist Antoine Lavoisier was the first to state the law of conservation of mass in his book. There is just a rearrangement in the atoms of substances for the formation of compounds. 7 min read Law of Constant ProportionsWe are all aware that matter is made up of atoms. Surprisingly, Greek philosophers proposed the concept of atom in the fifth century BC (BCE). Their notion, however, was philosophical rather than scientific. John Dalton proposed the first scientific theory of the atom. Few of Dalton's atomic postula 10 min read What is Atom?Atoms are tiny particles that comprise all the things in the known universe. Atoms of an element are responsible for all chemical reactions occurring in nature. We know that atoms are made up of three fundamental particles namely, ElectronsProtonsNeutronsThese particles are also called subatomic par 8 min read Atomic MassAtomic mass is the total mass of all subatomic particles of an atom, including protons, neutrons, and electrons. However, the mass of electrons is incredibly small, so it's typically neglected when determining an atom's overall mass. The unit commonly used to express atomic mass is the Atomic Mass U 9 min read How Do Atoms Exist?If you are going to build a house, you will undoubtedly need to manage a big number of bricks. This is due to the fact that it may be classified as a building component for your well-planned shelter. Similarly, atoms are the basic building units of stuff that surrounds us. Think of anything, and it 8 min read Cations vs AnionsIons are charged species that are formed by the transfer of electrons from the outermost shell. Ions are either positive or negative in nature depending on the overall charge of the ion. If an atom loses an electron it has excess proton forming positive ions whereas if an atom gains an electron it h 9 min read What are Ionic Compounds?In chemistry we usually come across terms called ions, anions, cations, ionic compounds study of such compounds is a must to understand various concepts. Let us understand why ions are formed generally, atoms are made up of particles called electrons, protons and neutrons. The number of electrons an 7 min read What are Monovalent Ions?Ions are a type of ion that is studied in science. Chemistry is made up of atoms and electrons that have gained or lost weight due to the removal or addition of one or more valence electrons, which results in either a positive or a negative charge. Ions with a negative charge are known as anions, wh 5 min read What are Divalent Ions?The study and research on the periodic table have come with various conclusions like the discovery of elements, atomic model, the structure of the atom, subatomic particles, etc. By the time there have been notable discoveries by scientists and researchers which made the study much relevant. The the 5 min read Trivalent Ions - Cations and AnionsThe theories proposed till now explains the physical and chemical properties of different elements found.The studies by different scientists have contributed to the expansion of the periodic table and described various other participants of atomic chemistry. Such as molecules, isotopes, ions, radica 5 min read Polyatomic IonsAn ion is a chemical entity that has a positive or negative charge of a certain magnitude. The term 'ion' can refer to atoms or molecules that have non-zero net charges attached to them. As a result, all ions contain either more protons than electrons in their overall atomic or molecule structure or 6 min read Formulas of Ionic CompoundsThe study of the modern periodic table shows all the elements dhows their own kind of nature. Among them, most of the atoms of the elements cannot exist freely in a stable state. Hence, for the purpose of obtaining stability, they share their valence electron with the atoms of other elements. This s 6 min read Chemical FormulaChemical formula is a way to describe chemical ratios of atoms that make up a specific chemical compound or molecule in chemistry. Chemical element symbols, numbers, and sometimes other symbols, such as parentheses, dashes, brackets, commas, plus (+), and minus (-) signs, are used to represent the c 6 min read Chemical Formula of Common CompoundsChemical Formulas of compounds are symbolic representations of their chemical composition. They tell us about which elements the chemical compound is made of and in what ratio. In this article, we will learn about the chemical formulae of some common compounds in detail. Table of Content What is Che 6 min read Molecular MassMolecular Mass is the mass of all the atoms present in a molecule. In ancient India and Greece, philosophers have first given the idea of atoms and deeply studied them. Around 500 BC.Everything around is made up of very small units these units are atoms in the language of science, very small in the 8 min read Mole ConceptMole concept is the method used to express the amount of substance. This has been experimentally proving that one gram atom of any element, as well as one gram molecule of any substance, contains the same amount of entities. The experimentally decided number is found to be 6.022137 × 1023. After the 10 min read Problems Based on Mole ConceptsIndian philosopher Maharishi kanad postulated that if a matter is divided into further smaller pieces, it will have smaller parts. However, there shall come a point when the matter no longer can be divided further and that smallest part is called Parmanu. By the end of the 18th century, scientists r 7 min read Dalton's Atomic TheoryIn the year 1808, the English scientist and chemist John Dalton proposed Dalton's atomic hypothesis, a scientific theory on the nature of matter. It asserted that all matter is made up of atoms, which are tiny, indivisible units. According to Dalton's atomic theory, all substances are made up of ato 8 min read Drawbacks of Dalton's Atomic TheoryThe idea of atoms dates back two millennia, long before John Dalton introduced the concept of atoms in 1803. Kanada, an ancient Indian philosopher, discussed the existence of indivisible particles, which he referred to as "anu." The rule of conservation of matter was introduced by French scientist L 6 min read Significance of the Symbol of ElementsAn element in chemistry refers to the purest form of a substance containing only atoms and cannot be broken down further by any means. These elements are classified according to their properties (both chemical and physical) and arranged according to their atomic number (Z) in the modern periodic tab 6 min read Difference Between Molecules and CompoundsMolecules are the smallest building blocks that form the matter around us. They are the simplest particles that carry the properties of matter. Molecules are joined together to form the Compound. A molecule is the smallest unit of matter formed by joining various atoms together whereas the compounds 6 min read How to Calculate Valency of Radicals?To construct the formulas of ionic compounds, we must first understand the valencies of the positive and negative ions that combine to produce the ionic compounds. As a result, we'll start with ion valencies. The valency of an ion is equal to its charge. If an ion has one unit charge, its valency is 5 min read What is the Significance of the Formula of a Substance?Everyone may think that if the atom is very tiny in size, what is its importance of it? So, this is because the entire world is made up of atoms and molecules. As known that one cannot see them with the naked eyes but they are always present around. They may be in the surrounding, substances that ev 5 min read Gram Atomic and Gram Molecular MassAvogadro's number is critical to understanding the structure of molecules as well as their interactions and combinations. e.g. because one atom of oxygen will combine with two atoms of hydrogen to form one molecule of water (H2O), one mole of oxygen (6.022 × 1023 of O atoms) will mix with two moles 7 min read Chapter 4: Structure of the AtomCharged Particles in MatterCan we deduce from these actions that rubbing two items together causes them to become electrically charged? The presence of charged particles in an atom was discovered thanks to the efforts of many scientists. By 1900, it was established that the atom was an indivisible particle that contained at l 8 min read What is Atom?Atoms are tiny particles that comprise all the things in the known universe. Atoms of an element are responsible for all chemical reactions occurring in nature. We know that atoms are made up of three fundamental particles namely, ElectronsProtonsNeutronsThese particles are also called subatomic par 8 min read Thomson's Atomic ModelThomson's Atomic Model is one of the fundamental models of the atom that tries to explain the working and structure of the atom. this model was proposed by famous Scientist JJ Thomson in 1904. Thomson during his cathode ray experiment proved the existence of a negatively charged particle called elec 6 min read Rutherford Atomic ModelRutherford Atomic Model was proposed by Ernest Rutherford in 1911. It is also called the Planetary Model of the Atom. It introduced the concept of a dense, positively charged nucleus at the center of an atom, with electrons orbiting around it, forming the basis for modern atomic theory. In this arti 6 min read Drawbacks of Rutherford's Atomic ModelIn Rutherford's Model of the Atom, Rutherford performed an experiment based on that experiment some of the hypotheses are given. At that time those hypotheses are considered revolutionary as there was an experiment to back that hypothesis. But as the experiment performed by Rutherford is rudimentary 10 min read Bohr's Model of an AtomNeil Bohr proposed the Bohr model and was based on the modification of Rutherford’s model of an atom. Rutherford's model introduced a nuclear model of an atom in which it was explained that the nucleus which is positively charged is surrounded by negatively charged particles called electrons. Bohr m 7 min read NeutronsNeutrons are fundamental subatomic particles of the atom. An atom is made up of electrons, protons and neutrons. James Chadwick, an English physicist, discovered the neutron in 1932. Neutrons are particles with no charge and higher mass. They are represented by n. They reside inside the nucleus of t 8 min read ValencyValency of an element is a measure of an atom's ability to combine with other atoms to create molecules or chemical compounds. The characteristics of an element that indicate how many more atoms can join one of its atoms in a covalent bond are known as valence, or valency, in chemistry. The term, wh 9 min read Valence ElectronsAny of the fundamental negatively charged particles in the outermost area of atoms that participate in the creation of chemical bonds are referred to as valence electrons. Changes in the atomic structure are confined to the outermost, or valence, electrons regardless of the kind of chemical connecti 10 min read Mass NumberMass Number of an atom is the total number of protons and neutrons present in an atom. We know that an atom consists of electrons, protons, and neutrons but the mass of the atom is contributed by protons and neutrons as the mass of electrons is very low hence it doesn't contribute to the mass of an 11 min read Relation Between Mass Number and Atomic NumberAtoms are the fundamental building blocks of matter, and they may combine in a variety of ways to produce various substances. You must be aware that all atoms are made up of electrons, protons, and neutrons. But did you know that the presence of these subatomic particles may explain an element's pro 8 min read IsobarsIsobars are a group of elements that have the same mass number but different atomic numbers. In an isobar, we have different numbers of protons but the same number of nucleons, i.e. the sum of the number of protons and neutrons in the nucleus of isobars of the elements are the same. An example of is 5 min read Why do all the Isotopes of an Element have similar Chemical Properties?The fundamental building units of matter are atoms and molecules. The existence of many types of matter is due to the various atoms that contain them. The atom was no longer seen as a simple, indivisible unit by 1900. It did, however, contain at least one subatomic particle, the electron. J.J. Thoms 6 min read Why Isotopes have different Physical Properties?The atom is divided into two parts: the atomic structure and the extra nucleus. Positively charged protons and neutral neutrons make up the atomic structure. Electrons in the extra nucleus are negatively charged. Atoms, like all elements and compounds, have mass. Because of protons, the mass of an a 5 min read What is Fractional Atomic Mass?The smallest possible amount of matter which still retains its identity as a chemical element, consisting of a nucleus surrounded by electrons is called an atom. These are the atoms that make up an element. An element is a material with the same number of protons in all of its atoms. Protons, electr 9 min read Radioactive IsotopesRadioactive Isotopes or Radioisotopes are the isotopes of the elements that are not stable, i.e. they emit some radiation and change the composition of their nucleus. Radioactive isotopes are defined as the isotopes of any chemical element that have different masses and unstable nuclei and release e 8 min read Discovery of ElectronsThe basic idea of the discovery of the elementary particles was generated by Dalton's Atomic Theory. John Dalton in 1808 gave the first scientific theory about atoms, in which, he stated that atoms are the smallest particle of any matter. They are indivisible and indestructible. According to Dalton 7 min read What is a Proton?Protons are the fundamental particles that reside inside the nucleus of any atom. They are the positive charge particle and are responsible for balancing the negative charge of the electron to make the atom electrically neutral. Proton was discovered by the famous scientist Ernest Rutherford. Atoms 6 min read Rutherford's Alpha Scattering ExperimentRutherford's Alpha Scattering Experiment is the fundamental experiment done by Earnest Rutherford's Alpha Scattering Experiment that gives the fundamental about the structure of the atom. Rutherford in his experiment directed high-energy streams of α-particles from a radioactive source at a thin she 6 min read Atomic NucleusThe nucleus of an atom is a small, dense, round region located in the centre of an atom. It has two subatomic particles, protons and neutrons. Protons are electrically positively charged ions having a mass of approximately one atomic mass unit (amu). Neutrons are electrically neutral.The atomic nucl 10 min read How did Neil Bohr explained the Stability of Atom?Bohr model of the atom was explained by Neil Bohr in 1915. It came into existence with the modification of Rutherford’s model of the atom. Rutherford’s model introduces the nuclear model of the atom, in which he explained that a nucleus (positively charged) is surrounded by negatively charged electr 7 min read Electron ConfigurationElectron Configuration of an element tells us how electrons are filled inside various orbitals of the atom. The distribution of electrons inside various orbital of atoms is very useful in explaining various properties of the atoms and their combination with other atoms. The electron configuration of 8 min read Potassium and Calcium - Atomic Structure, Chemical Properties, UsesAn atom is the smallest part of an element or compound that takes part in a chemical reaction. They are made of tiny particles known as protons, neutrons, and electrons. The Greek philosopher Democritus was the first person to use the term atom. The structure of the atom was discovered by John Dalto 8 min read Noble GasInert gases are chemically unreactive. Noble gases, also termed inert gases are group 0 elements. There are six types of noble gases, helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radioactive radon (Rn). The noble gases are the type of elements belonging to group 18. Under standa 4 min read What is meant by Chemical Combination?The composition of an element's nucleus and the arrangement of electrons around it are referred to as its atomic structure. Protons, electrons, and neutrons are the building blocks of matter's atomic structure. The nucleus of the atom is made up of protons and neutrons, which is surrounded by the at 6 min read Difference between Electrovalency and CovalencyWe're all familiar with how electrons in an atom are organised into orbitals or shells. Valence electrons are the electrons that exist in the atom's outermost orbit. According to the Bohr-bury theory, the outermost shell may hold a maximum of 8 electrons. When the outermost shell is entirely filled, 8 min read Like