History of the Periodic Table Essay

apologize how scientific observations led to the development of, and changes to, the biennial table. -Dmitri Mendeleev- first biennial table, unionised 63 known constituents according to properties, organized into rows and columns and wrote heel, bulk, and chemical properties on from each integrity -Julius Lothar Meyer- independently worked in Germany, similar to Mendeleev -Henry Gwyn Jeffreys Moseley- Worked with Ernest Rutherford, experimented with 38 metals, he assemble that the autocratic quiver of each elements nucleus increased by one from element to element as they were arranged in Mendeleevs periodic table, lead to modern definition of corpuscleic number ( of protons in atoms nucleus) and the recognition the atomic number was basis for government activity of periodic table. come upon the organization of the modern periodic table.Arranged from left-hand(a) to right in rows (periods) by increasing atomic number and nobble to bottom in columns (groups) found on similar chemical propertiesLesson 03.02 stem Names and PropertiesComp ar and contrast the properties of metals, metalloids, and nonmetals. -Metals- expert conductors of heat and electricity and think over light and heat, most luster (shine) and most are malleable (hammered or rolled into sheets) -Non-metals- poor conductors of heat and electricity, most are gas at room temperature, those that are solid are not malleable -Metalloids- a semiconductor (conduct electricity better than non-metals moreover not as good as metals), some characteristics of metals but more like nonmetalsIdentify groups and sections of the periodic table by group name and common properties. 3.02 notesLesson 03.03 Periodic TrendsDescribe and explain the trends for effective nuclear foreign mission, atomic radius, noggin radius, and ionization postal code across a period and down a group. -Effective Nuclear Charge- the charge (from the nucleus) felt by the valence negatrons after you have taken into dep end the number of shielding negatrons that surround the nucleus. -Atomic radius- half the distance amidst the centers of deuce atoms of that element that are bonded together -Ionization Energy- the free energy required to remove one electron from an element, resulting in a substantiating ion. - loft radius- One-half the diameter of an ion.A positive ion is called a cation, and a negative ion is called an anion. Nonmetals unremarkably become anions and metals usually become cations.Predict the properties of an element based on the known patterns of the periodic table. Use periodic tableDescribe and explain the periodic trends for electron affinity (honors). Electron affinity-The energy involved when a neutral atom gains an electron Becomes more negative (more energy is given off) for each element across a period from gathering 1 to sort 17 because of an increase in effective nuclear charge. Becomes less negative (more positive) divergence down a group, because each electron is being added to a higher(prenominal) energy level farther from the nucleus.Explain the exceptions to the trend across a period for ionization energy (honors). Noble gases in Group 18 all have positive electron affinity values. The noble gases must(prenominal) be forced to gain an electron because they already have a full valence energy level. The alkaline earth metals in Group 2 and the nonmetals in Group 15 both have electron affinity values close to zero due to electron antagonism and effective nuclear charge. Nitrogen, in Group 15, does not form a stable -1 ion because when an additional electron is added to nitrogens valence energy level, it is added to a 2p orbital that already has one electron. The weak draw between the added electron and nitrogens nucleus is why there is not much energy given off.Lesson 03.04 Valence Electrons and BondingDefine and equivalence garret and covalent bonding.-Ionic Bond- A chemical bond that results from electrostatic attraction between posit ive and negative ions, electrons are given up by one atom and gained by another atom, and then those atoms are attracted to each other.Between a metal and nonmetal. -Covalent bond- Electrons are shared between devil atoms, neither atom completely gains or loses electrons. Between two nonmetals. mend your knowledge of the periodic trends to the chemical bonding exhibited by various elements.Lesson 03.05 Ionic Bonding and Writing FormulasDetermine an elements bean charge based on its location on the periodic table. Group 1- 1+Group 2- 2+Group 3- 3+Group 4- 4+Group 5- 3-Group 6- 2-Group 7- 1-Group 8- non-reactive noble gases salve the correct ionic convention when given two elements that bond ionically. Use question to a higher place and periodic tableLesson 03.06 Covalent Bonding and Lewis StructuresDetermine how many covalent bonds an atom needs in order to fill its valence shell, using the periodic table. Must get to 8 valance electrons.Ex. Group 17 needs one more valance elect ron group 6 needs 2 more valance electronsDraw correct Lewis structures to poseur covalently bonded molecules when given the name or design of the molecule.Describe your observations and conclusions from the virtual lab.Lesson 03.07 intermolecular ForcesUse VSEPR theory to predict the shape of a molecule based on its Lewis structure. The VSEPR theory is about geometry of fluxs and electron location.Compare and contrast intermolecular forces (London dispersion, dipole-dipole, hydrogen bonding, and ion-dipole).London dispersion forces occur between all molecules and particles but are the only force of attraction between nonglacial molecules or noble gas atoms. These forces are the weakest of the intermolecular forces. The London dispersion forces are caused by the motion of electrons. Dipole-dipole forces are electrostatic interactions of permanent dipoles in cold molecules.The attractive forces that occur between the positive end of one polar molecule and the negative end of anot her polar molecule turn tail to align the molecules to increase the attraction. Hydrogen bonding is a particularly bulletproof dipole-dipole interaction in which hydrogen is covalently bonded to a highly electronegative element, and attracted to the in truth electronegative element in another molecule. It occurs only in molecules containing N-H, O-H or F-H bonds. Ion-dipole forces are attractive forces that result from the electrostatic attraction between an ionic compound and a polar molecule. This interaction is most commonly found in solutions, especially in solutions of ionic compounds in polar solvents, such as water.Identify the intermolecular forces experienced by different compounds. intramolecular Forces The forces of attraction that occur between individual molecules.Lesson 03.08 Naming CompoundsCorrectly name covalent compounds, ionic compounds, and acids when given their laws. A metal forms a positive ion (cation) and a nonmetal forms a negative ion (anion). The cati on and anion combine to form an ionic compound, more specifically referred to as a binary ionic compound.Write the formulas for ionic compounds, covalent compounds, and acids from their names.Name hydrates or write the formula of a hydrate when given its name (honors). Same prefixesLesson 03.09 Molar Mass of Compounds await the molar mass of compounds from the formula.Determine empirical formulas from percent by mass or mass data.Empirical formula The formula of a compound in which the subscripts represent the lowest whole-number ratio of the atoms.Determine the molecular formula from the empirical formula and molar mass of a substance. No wrapCalculate the molar mass of a hydrate and determine the formula of a hydrate from experimental data (honors). H2O- 18.015Determine the empirical formula of a compound from the mass of the productsproduced in experimental reactions (honors).