Atomic Structure And Bonding - Case Study Example

Atomic Structure and Bonding Name University An atom can actually be defined as the smallest particle of a specific element that cannot exist on its own. Every element is composed of atoms and it turn the atoms are composed of protons, the electrons and the nucleus. The elements have varying numbers of protons and the electrons depending on their atomic number. The first element in the periodic table is called the hydrogen, hydrogen has been established to consist of a single electron and proton, therefore for the atom to be stable, it needs to combine with another atom to form a molecule and thus be stable. The first shell of very atom is normally filled with at most two electrons to be stable hence when the two hydrogen atoms share their single electrons they become stable and can no longer react. Scientists have accurately established that atoms achieve status of stability by either losing gaining or sharing of electrons. We have noted that every atom actually consists of protons which are the positive charges and the electrons which are normally the negative charges. The nucleus of an atom is normally located at the central point or simply at the centre of the shells which accommodate the electrons which normally revolve around the nucleus. Nucleus comprises of the neutrons and the protons. Addition of the neutrons and the protons gives as the atomic mass of any specific element in the periodic table. Figure: A structure of an atom It should be noted that neutrons are normally neutral in the terms of charges and that is the reason why they effectively co-exists with the protons at the nucleus. From the above figure, the blue and orange balls represent the nucleus which comprises of neutrons and the protons. The reddish small ball that actually revolves around a ring structure in the figure represents the electron. Elements that exist on the planet earth are normally arranged in standard universal table called the periodic table. The periodic table was brought forward by a Russian national. He arranged the elements according to their atomic masses and electro negativities. Also he took into consideration the chemical states of those elements. Figure: The periodic table The periodic table comprises of eight groups. The eight groups are (IA, IIA, IIIA, IVA, VA, VIA, VIIA, VIIIA). This actually means that as we move from the group number one to the next group, there is an increase in the number of electrons in the outermost shell of the atom. It should be noted that elements in group one have a single electron in their outermost shell, while those in the second group have two electrons, those in group three have three electrons in the outermost shell while those in the last group which is normally group eight have maximum possible number electrons in their in their outermost shell meaning that they have already achieved stability. Group eight elements do not need to react to achieve any sort of stability as they are already stable. The group eight elements are called the inert gases and they include elements such as neon, helium, argon krypton gases. The electronegativity of the elements in the periodic table increases from the left side of the table to right hand side. Elements on the right hand side of the table are more electronegative that the elements on the left hand side of the periodic table. The term electronegativity can be definitely be defined as the ability of any element to displace electrons of another element to achieve stability. For example when we carry out a reaction of the elements sodium and chlorine, they will react to form sodium chloride. The compound which is the product is stable and has been arrived at by losing of the single electron in the outermost shell of the sodium element and the gaining of the extra electron by chlorine to achieve stability. Elements either loose or gain electron to achieve stability as portrayed by the sodium and the chlorine elements. In between the elements of the groups two and three there exist a group of transitional metals. Transitional metals are metals like copper, manganese, zinc. Transitional metals are simply the metals that we essentially use in many of the industrial applications in our industries. In the figure showing the periodic table above, the transitional metals are contained in the following groups (IB, IIB, IIIB, IVB, VB, VIB, VIIB and VIII). Another very important aspect of the periodic table that should be noted is that elements in the group one become more reactive as they tend down the periodic table. For example let`s take into consideration the four elements of the group one which are hydrogen, lithium, magnesium and potassium. Their electronic configurations are; 1, 2.1, 2.8.1 and 2.8.8.1, we note that they all have just a single electron in their outermost shell and that the number of shells increase down the group. Potassium is arguably more reactive that magnesium, magnesium is in turn more reactive that lithium and at last lithium is definitely more reactive than hydrogen. What brings about the difference in the intensities of the reaction of the elements? The real approach to this notable difference is the reduction in the forces that binds the electron to the nucleus. We have actually noted that the atomic radius has progressively increased down the group one which is also a similar trend for the other groups. Any increase in the number of shells that contain the electrons consequently implies an increase in the atomic radius. As the atomic radius increases, the forces that bind the electrons to the nucleus of the atom reduce making it easier for the particular atom to lose an electron. A lesser amount of energy is required to enable the element loose the electron in the outermost shells. Therefore this is the reason while the potassium element is most reactive of the four elements under consideration. Valence electrons are the term used to refer to the electrons that occupy the outermost energy level or shell. Therefore you can state that the group one elements have a single valence electron while group two elements have two valence electrons. We therefore conclude that it is only the valence electrons that are normally involved in reactions between any elements and also that vast amounts of energies are liberated when elements loose electrons during reactions. Compounds are usually formed when two or more elements react in a chemical reaction. Therefore compounds can be termed as mixtures of elements. Examples of compounds include; sodium hydroxide, ammonia, and water. Water is a compound that comprises the oxygen and the hydrogen elements, ammonia comprises of nitrogen, hydrogen and oxygen compounds whilst the sodium hydroxide comprises of sodium, hydrogen and oxygen compounds. Compounds utilize various types of bonding means so that they remain stable under normal atmospheric conditions. Compounds have been established to utilize the following types of bonds; ionic bonds, metallic bonds, the covalent bonds, the fluctuating or the permanent dipole bonds and lastly the hydrogen bonds. Various compounds utilize these bonds to remain stable under ordinary conditions of temperatures, pressure amongst other variables of the weather. Ionic bonding is a type of bonding that exists when a metallic element essentially reacts with a non-metallic element of the modern periodic table. For example when a metallic element such as sodium reacts with a non-metallic element such as chlorine, they will actually form a compound which sodium chloride that entails the ionic bonds. We can actually conclude that ionic bonds result when an electropositive element combines with an electronegative element. In our particular case, the electropositive element is the sodium whilst the electronegative element is the chlorine. Ionic bonds are strong hence the reason why ionic compounds have high lattice energies of the rage of 600-3000 KJ/mol and also the high melting temperatures. The next popular type of bond in chemical compounds is the covalent bond. This is a type of bond eminent in non-metallic elements such as carbon, nitrogen, oxygen and silicon elements. This type of bonding exits in elements that have small differences in their electronegativity. Molecules of elements such as hydrogen, oxygen chlorine have this type of bond. The atoms of those specific elements are bonded together in the molecules by this type of bond. It has been established that this bond is rather weak and it is the major constituting reason why the elements portraying this type of bond have very low melting and boiling temperatures. Most of the compounds or molecules bonded by this particular type of bond exist as gases at the normal room temperatures. This a type of bond that results from sharing of the valence electrons Figure: A view of covalently bonded silicon molecule The third type of bond under consideration is the metallic bonding. This type of bonds only exists in metals either in their pure form or as alloys. Metals such as iron, copper, steel, brass, bronze and others all utilize this type of bond. This type of bonding is very strong and thus the reason why metals have arguably high melting and boiling temperatures. It should be precisely noted that although diamond has high melting temperatures, it does not entail this type of bond. In metals, the valence electrons are weakly bonded and they can be termed as free electrons which can actually move about. Metals have good electrical conductivity because the electrons are non-localized and can move about when an electrical voltage is applied, metals have also high thermal conductivities since the electrons carry with themselves the energy. Metallic bonds are non-directional hence the reason why metals are ductile since when they are bend or distorted in particular manner, the electrons can move about to compensate. The next type of bond is what is referred to as the secondary bonding that entails both the fluctuating diploes and the permanent dipoles. The permanent dipole bonds are bonds that are normally formed when molecules that have permanent diploes combine chemically. The permanent dipole bonds are arguably weak intermolecular bonds which are objectively tasked with bonding the molecules together in their respective compounds. An example of a permanent dipole bond is the bonds that exist in the molecules of water and the hydrogen chloride compounds. They are normally weak in nature. Hydrogen bond is a type of bond formed between two permanent dipoles in the very adjacent water molecules. This specific bond is only evident in water molecules since it where the permanent dipoles are likely to interact and consequently form the bond. Figure: Hydrogen bonds between adjacent water molecules In the above figure, two small balls are attached to a big ball. The big ball represents the oxygen atom whilst the two small balls then represent the hydrogen atom. This is so since a molecule of water entails two hydrogen atoms and a single oxygen atom. The water molecules are attracted together and they are weakly bonded together by the hydrogen bonds which are exhibited by the arrows. Therefore this particular type of bond is characterized by low melting temperatures, low coefficient of expansion and also low modulus of elasticity. Fluctuating dipole bonds result when some weak electric dipole bonding essentially take place amongst the atoms as a result of instantaneous distribution (asymmetrical) of the particulate electron densities around the nuclei. The electron density is always continuously changing. The secondary bonds have the lowest bond energies amongst all other types of bonds and they directional bonds meaning that electrons are localized and cannot move hence properties such as ductility are indeed very poor in compounds that portray this kind of bonds. We can therefore conclude that an atom is the smallest unit of an element that cannot exist on its own whilst a molecule is also the smallest unit of an element that can actually exist o its own. We have also noted that various types of bonds are utilized to bind the atoms and molecules together in either the element or the compound status and these bonds are of varying strengths with metallic bonds being the strongest and secondary bonds the weakest. We have also noted that valence electrons I s the group of electrons that is actually involved in the chemical reactions and that elements either lose, share or gain these electrons to achieve stability. References Steudel, R. (1977). Chemistry of the non-metals: With an introduction to atomic structure and chemical bonding. Berlin: W. de Gruyter. Basic Systems, inc., New York., & Dawson, C. R. (1962). Chemistry I: Atomic structure and bonding. New York: Appleton-Century-Crafts. Hill, G., Holman, J., & Audio Learning, Inc. (1970). Atomic structure and bonding. London [England: Audio Learning. Barrett, J. (2002). Structure and bonding. New York, NY: Wiley-Interscience. Seel, F. (1963). Atomic structure and chemical bonding, a non-mathematical introduction. London: Methuen. Read More

Group eight elements do not need to react to achieve any sort of stability as they are already stable. The group eight elements are called the inert gases and they include elements such as neon, helium, argon krypton gases. The electronegativity of the elements in the periodic table increases from the left side of the table to right hand side. Elements on the right hand side of the table are more electronegative that the elements on the left hand side of the periodic table. The term electronegativity can be definitely be defined as the ability of any element to displace electrons of another element to achieve stability.

For example when we carry out a reaction of the elements sodium and chlorine, they will react to form sodium chloride. The compound which is the product is stable and has been arrived at by losing of the single electron in the outermost shell of the sodium element and the gaining of the extra electron by chlorine to achieve stability. Elements either loose or gain electron to achieve stability as portrayed by the sodium and the chlorine elements. In between the elements of the groups two and three there exist a group of transitional metals.

Transitional metals are metals like copper, manganese, zinc. Transitional metals are simply the metals that we essentially use in many of the industrial applications in our industries. In the figure showing the periodic table above, the transitional metals are contained in the following groups (IB, IIB, IIIB, IVB, VB, VIB, VIIB and VIII). Another very important aspect of the periodic table that should be noted is that elements in the group one become more reactive as they tend down the periodic table.

For example let`s take into consideration the four elements of the group one which are hydrogen, lithium, magnesium and potassium. Their electronic configurations are; 1, 2.1, 2.8.1 and 2.8.8.1, we note that they all have just a single electron in their outermost shell and that the number of shells increase down the group. Potassium is arguably more reactive that magnesium, magnesium is in turn more reactive that lithium and at last lithium is definitely more reactive than hydrogen. What brings about the difference in the intensities of the reaction of the elements?

The real approach to this notable difference is the reduction in the forces that binds the electron to the nucleus. We have actually noted that the atomic radius has progressively increased down the group one which is also a similar trend for the other groups. Any increase in the number of shells that contain the electrons consequently implies an increase in the atomic radius. As the atomic radius increases, the forces that bind the electrons to the nucleus of the atom reduce making it easier for the particular atom to lose an electron.

A lesser amount of energy is required to enable the element loose the electron in the outermost shells. Therefore this is the reason while the potassium element is most reactive of the four elements under consideration. Valence electrons are the term used to refer to the electrons that occupy the outermost energy level or shell. Therefore you can state that the group one elements have a single valence electron while group two elements have two valence electrons. We therefore conclude that it is only the valence electrons that are normally involved in reactions between any elements and also that vast amounts of energies are liberated when elements loose electrons during reactions.

Compounds are usually formed when two or more elements react in a chemical reaction. Therefore compounds can be termed as mixtures of elements. Examples of compounds include; sodium hydroxide, ammonia, and water. Water is a compound that comprises the oxygen and the hydrogen elements, ammonia comprises of nitrogen, hydrogen and oxygen compounds whilst the sodium hydroxide comprises of sodium, hydrogen and oxygen compounds. Compounds utilize various types of bonding means so that they remain stable under normal atmospheric conditions.

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