Magnesium Oxide Chemistry Report Essay

In chemistry, compounds can be distinguished by using the verifiable formula. The formula provides the simplest corroboratory integer ratio of elements in a compound. The empirical formula is largely useful in determining the ratio of elements within ionic compounds where the structure is of a non-directional nature of bonding where either ion at any time could be surrounded by 4, 6, or 8 oppositely charged ions. This creates a descriptor of endlessly repeating lattice of ions they do non exist as a free unit of atoms but in crystal lattices with repeating ions in specific ratios which is why empirical formula is used as a form of identification for defining an ionic-bonded substance.Calculating the empirical formulaTo calculate the empirical formula for when two reactants undergoes a chemical reaction, the following 5 steps should be taken 1. Record the hoi polloi of all the elements present in a given compound. 2. Convert the pluralityes into bulwarks (dividing by atomic we ight in grams). 3. Then divide through by the smallest physical body of moles to get a ratio. 4. It the total game are not full-length quashs, multiply by a suitable small factor to get a whole number. 5. Finally, round off the numbers in the previous step if applicable to get the prime numbers which indicates the empirical formula. To demonstrate with a simple example The molecular formula of butane is C4H10, to a greater extentover as the ratio of carbon atoms to hydrogen atoms is 410 it can be reduced to the ratio of 25. We can see that it is the simplest ratio piece remaining as an integer. Butane can now be represented in empirical formula as C2H5.Regarding the Mole and its formulaThe mole is the quantity of a substance which contains as many elementary units (atoms, ions, molecules) as there are atoms in exactly 12 grams of carbon-12 isotope. A mole of an element is the corporation in grams that is numerically liken to the atomic weight. Also, a mole of a compound is the sess in grams that is numerically equal to the molecular weight. In simpler wordsA mole of a substance is simply the atomic / molecular weight in grams. eg Amole of copper (atomic weight 63.6) is 63.6grams.Therefore in a diagramThe number of atoms or molecules in a mole of any substance is the Avogadro Constant which is 6.02 x . The molar mass is taken to be the proportional atomic mass of an element which is the average mass of atoms present in any naturally occurring element relative to the mass of one atom of carbon-12 isotope taken as exactly 12 which gives formula weight (sum of the atomic weights of the atomic species as given in the stated formula for the compound.) The quantitative stoichiometric relationships judicature mass and amount is used in the following taste regarding the burn reaction of milligram metal. magnesium is reacted with oxygen from air in a contained melting pot, and the pack before and after the oxidation is measured. The resulting spate a re used to calculate the experimental empirical formula of magnesium oxide, which is therefore compared to the theoretical empirical formula. A crucible and Bunsen burner pull up stakes be used to heat magnesium metal for burning.EquipmentAIMThe purpose of this experiment is to perform an experiment of the combustion of milligram and gather precise and accurate data of masses and olibanum find the number of moles of the substance through the stoichiometry mole equation in order to prize the empirical formula of milligram Oxide.METHOD1 The Bunsen burner was set up with the tripod. The pipe clay triangle was placed over the tripod, ensuring that it is secure. 2. The crucible containing the magnesium was positioned in the pipe clay triangle securely with the eyelid on. 3. The gas was turned on and the Bunsen burner ignited to a blue flame. 4. The crucible was shoot strongly for 5minutes until the bottom of the crucible glowed red over the blue flame to rid of contaminants. 5 . The flame was removed and to cool the crucible with lid.6. A piece of magnesium about 5 cm long was cut.7. The surface of the magnesium ribbon was thoroughly cleaned with steel wool and its appearance was recorded 8. The cooled crucible and lid was weighed(1st mass to 2dp) 9. The cleaned magnesium was coiled to fit inner the same crucible and covered with the same lid. 10. The crucible containing the magnesium with the lid on was weighed. (2nd mass to 2dp) 11. The crucible containing the magnesium was positioned without the lid onto the pipe triangle setup, ensuring its security. 12. The gas was turned on again and the Bunsen burner was ignited to a red flame (air hole fully open). 13. As the magnesium began to glow, the crucible was covered with its lid guardedly with pair of tongs. 14. Heat strongly for about 10 minutes lifting the lid a little VERY carefully occasionally to admit oxygen. 15. Keep heating and lifting the lid until ALL the magnesium turns into gray-white powd er or until no further reaction can be witnessed to contain complete reaction (for around 5 minutes) 16. Turn off the gas and allow the apparatus to cool.17. Weigh the completely cooled crucible containing magnesium oxide with the lid carefully. (3rd mass to 2dp)RISK ASSESSMENTWear safety glasses. It is important to admit eye protection during the combustion of milligram as the burning magnesium in the crucible produces a very b pay off light which emits a harmful intensity of UV light which can practice eye discomfort or damage. Do not inhale the smoke produced when Magnesium is burned. Magnesium Oxide smoke can cause irritation in the nose, eyes and lungs and in large amounts, may cause metal fume fever. Use tongs at all times when handling hot objects. Careful handling of hot equipment such as the crucible and its lid during the heating is important as the very high temperature can burn skin due to improper or insecure handling. Do not cool the crucible or lid under cold wat er immediately after heating. This can cause the equipment to crack and the shards may easily thrust the skin. If the crucible crack during the experiment, it is vital that the person discontinue any progress with the experiment and proceed to clean the rugged equipment away immediately and place into the broken glass bin.RESULTSMASSESBEFORE HEATINGAFTER HEATING press of Magnesium0.08gn/aMass of oxygenn/a0.05gMass of Magnesium Oxiden/a0.13gMass of crucible + lid24.36g24.31gTotal mas of Mg oxide in crucible + lidn/a24.44gTotal mass of crucible + lid + magnesium24.39gn/aPercent composition of Magnesium in compoundMass of Mg in 1 mole/ Mass of MgO in 1 mole% composition of atomic number 8 in compoundUpon observation, the 5cm Magnesium ribbon had a slightly greasy texture and a brittle and coarse surface. It had a hazy, dark metallic sheen to its appearance. After polishing its surface front and back thoroughly with steel wool, there was a change in its appearance. It had a shiny and glossy silver lustre with a smooth clean surface, no longer feeling waxy. The steel wools purpose was to remove the oxide layer of carbonate and sulphate which has coated the Magnesium ribbons surface due to its slow oxidation in air with CO2 and SO2 and other possible contaminants (which may have caused the strip to feel greasy). The oxide coating on the Magnesium would have made the ribbon more resilient to ignite immediately and thus hinder the combustionof the metal and prolong the time it takes for the metal to fully combust. The procedure of rubbing Magnesiums surface with steel wool was beneficial in order to expose fresh Magnesium to facilitate the contact of the ribbon with the flame quicker and thus a faster complete combustion.The crucible and lid used had minimal surface stains on the outside however it was heavily contaminated with residual substances towards the inside base. By firing the equipment under a blue Bunsen flame thoroughly, it became apparent that any moist ure or volatile materials present are burned off by 5minutes to reveal a clean crucible free of stains or moisture. The purpose of firing the crucible at a high temperature was to chop-chop eradicate any stubborn chemicals which may have resisted cleaning by water, as well as any moisture the crucible may make water to provide a clean and dry equipment which can procure accuracy and validity of calculations of masses.In order to activate the reaction of Magnesium, a source of energy was needed. The flame provided a source of heat which prompted a chemical reaction to proceed. When the magnesium was supplied with energy in the crucible, it reacted with a limited quantity of oxygen by using the lid to prevent high exothermic energy (Magnesium would react vigorously if heated in the presence of unobstructed air flow) and the escape of any magnesium oxide during the combustion. It became oxidized to become an ionic compound Magnesium Oxide.After the experiment of combusting Magnesi um, the residue in the crucible is observed to be in a fine white powder form of Magnesium Oxide, an ionic compound. The exothermic reaction of combusting Magnesium produced a very bright light within the crucible due to the rapid heating of the Magnesium, where it quickly absorbs energy through ionisation. Magnesium ionises to become a cation while group O ionises to an anion, forming an ionic bond due to electrostatic forces.DATA ANALYSISIn this experiment, through the combustion reaction of Magnesium, a word equation forms amid Magnesium, type O and the ionic compound MagnesiumOxide. Magnesium + Oxygen Magnesium OxideWhen ignited, magnesium has reacted with oxygen to form the products Magnesium Oxide. By taking the mass of equipments used and its mass during and after the reaction, the mass of Magnesium, Oxygen and Magnesium Oxide can be calculated. The mass of the reactants should very closely or mirror the mass of products by Law of Conservation of Mass.COLLECTING MASSES(ma ss 1) Crucible + lid = 24.31g (weight after ridding of visible contaminants on crucible) (mass 2) Crucible + lid + magnesium = 24.39g (weight after polished magnesium is placed in fired crucible + lid) (mass 3) Crucible + lid + product = 24.44g (weight of reacted substance MgO in the crucible with lid) To calculate the mass of Magnesium metal = Mass 2 Mass1 = 24.39g 24.31g Mass of Magnesium = 0.08gTo calculate the Mass of Oxygen incorporated = Mass 3 Mass 2 (the increase in mass corresponds to the mass of oxygen) = 24.44g 24.39g Mass of Oxygen = 0.05gTo calculate the mass of oxide product make = Mass 3 Mass 1 (to validate through natural law of conservation of mass) = 24.44g 24.31 Mass of Magnesium Oxide = 0.13gNow that the mass of each substance which took variance in the reaction is found, the number of moles can be found through the relationship below. Number of Moles = Mass / Molar MassOrN =The number of Moles can be calculated by knowing the mass of individual substance s in the experiment divided by the molar mass (given on the biannual table as atomic mass number) to experimentally determine empirical formula for the ionic oxide.CONVERTING TO MOLESNumber of Moles of Magnesium N = 0.08g / 24.31g/mol= 0.00329082692 moles Number of Moles of Oxygen N = 0.05g/16x2g/mol (oxygen is doubled as it exists as a diatomic molecule) = 0.0015625 molesDIVIDE BY SMALLEST MOLE VALUEThe number of moles of Magnesium is larger than the number of moles of Oxygen 0. 00329(to5dp) moles 0.00156 (to5dp) molesBy dividing each by the smallest mole value of 0.00156 of Oxygen, Magnesium and Oxygen mole ratio is calculated respectively. Magnesium Mole ratioOxygen Mole ratio= 2.11(to2dp)= 1Multiply UNTIL WHOLEThe next step is to multiply any decimal numbers by a small whole number and do the same for the other whole number ratio until the decimal number reaches a near whole number (which can then be rounded up). Magnesium Mole ratio is in a decimal number of 2.11, and as it i s very close to 2(with 0.11 extra of being a whole number), the number 2.11 is round down to 2 so the process of multiplying until whole is omitted. We obtain the mole ratio as follows Magnesium Oxygen 2 1 With 2 moles of Magnesium reacting with 1 mole of Oxygen, this should suggest 2 moles of MgO after balancing the equation. 2Mg(s) + O2(g) 2MgO(s) To confirm, the law of conservation of mass is applied which states that in a balanced equation, matter is conserved Total mass of reactants = Total mass of productsThus, by adding the mass on the left hand side (reactants), it should equal the right hand side (product). Magnesium + Oxygen = 0.08g + 0.05gMagnesium Oxide = 0.13g It is found that there is no difference in mass between the left side of 0.13g of Magnesium + Oxygen to the right side of 0.13g of Magnesium Oxide in the equation considering the possibility of experimental errors, which represents a positive outcome as an theoretical equation is naturalised and proved to be t rue. The empirical formula for Magnesium oxide is MgO, which is the correct formula and thus the aim of this experiment has been met.DISCUSSIONThe experiment demonstrated the ability for a substance to exist in the empirical formula composition as the simplest ratio of elements present in the compound. It also demonstrated quantitative stoichiometric relationships between the number of moles, mass and molar mass in a chemical reaction. The theoretical result for the combustion product of Magnesium and Oxide is MgO, which in comparison to the experiment result of MgO was proven to be the same. This experiment had demonstrated the basic chemical reaction and the change in states between elements in order to form a stable ionic compound. Through the ionic bond between a metal and a non-metal, Magnesium Oxide was the product of two reactive elements Magnesium and Oxygen. hypothetic laws of conservation of mass and constant composition, lead to the arrangement of a relationship between the reactants (Magnesium and Oxygen) and product (Magnesium Oxide). The total mass of the products of a reaction must equal the total mass of the reactants. (0.8+0.5 = 0.13) The coefficient of a substance indicated the amount of portions each substance existed in, based on the law of conservation of mass. (2 moles of Magnesium, 1 mole of Oxygen, and 2 moles of Magnesium Oxide).And lastly, the empirical formula of a compound gave the lowest whole-number ratio of the atoms that is the identical with the mass ratios measured by experiment. (MgO) Any portion of a compound will have the same ratio of masses as the elements in the compound. Metal and a non-metal reaction of 2 substances taking place Ionic bond of elementschanges in states and formation of a stable compound the construction of an unbalanced chemical equation - evaluation of masses of the reactants to products the law of conservation of mass/and constant composition -the masses of left sideequals right side provide moles t o balance the overall equation establish empirical formula for end product. 3 experimental errors that may have effect on resultMagnesium Oxide forms fumes which may escape the crucible when allowing a passage for oxygen to pass when the lid is lifted. Incomplete combustion of Magnesium (as no stirring rods was used to check/sift through the oxide to prevent calculation errors) Unthorough firing of crucible and lid (due to contact between tongs and crucible, certain areas may be missed) 3 improvements to method to improve resultsMonitor the reaction of Magnesium with oxygen carefully, and keep the lid in place on the crucible containing the magnesium instead of off in step 11. Heat the magnesium for five minutes longer, lightly rotating the crucible at its base to ensure complete combustion. Fire the crucible and the lid twice to ensure that its completely dry and clean.CONCLUSIONAn experiment was performed to calculate the empirical formula of magnesium oxide by comparing the masse s of solid magnesium metal to the magnesium oxide solid product in a crucible. The concept of stoichiometry mole equation leads to finding the empirical formula of magnesium oxide. One major finding during the experiment was that burning magnesium caused its mass to increase as it reacted to oxygen. The amount of mass increase is proportional and able to be calculated through weighing the mass of product Magnesium Oxide and subtracting the original Magnesium mass to calculate the mass of Oxygen which partook in the combustion.The Empirical formula had indicated the proportion of Magnesium to oxygen (11) and identifies the compound to be Magnesium Oxide. The balance was very accurate in taking precise measurements of masses and the supervision of the experiment during the burning had been careful to prevent any loss of Magnesium Oxide mass to escape which in turn caused my mass results to apply to the law of conservation of mass without any experimental errors.