The aim of this experiment is to find the formula of magnesium oxide. Magnesium burns bright red but when it mixes with oxygen will form a white solid magnesium oxide (magnesium looks doll red). The mass of magnesium oxide will be more than the mass of magnesium because oxygen from the air joined with magnesium. To find out how much oxygen has joined with the magnesium, we just need to weigh the magnesium oxide after reaction and compare the value with mass of the magnesium before reaction. To work out the formula of the magnesium oxide, we need relative atomic masses and number of moles of magnesium and oxygen.
(b) Calculate the volume of 0.2M UO3- needed to react with 20.00 cm3 of 0.1M Cr2O72-. 3. 24.40 g of hydrated iron(II) sulphate, FeSO4.xH2O was dissolved and made up to 1.0 dm3 of aqueous solution, acidified with sulphuric acid. 25.00 cm3 of the solution was titrated with 20.00 cm3 of 0.022M potassium manganate(VII) solution for complete oxidation. a) Write the equation for the reaction.
Find the mass of the contents of the crucible. This is your new compound of magnesium. The mass of the magnesium oxide compound is 0.971. I got this answer my subtracting the mass of the crucible lid and contents after the reaction with the mass of the crucible lid and contents after the reaction, which equals 0.382. Then I added 0.382 to the mass of magnesium ribbon, which is 0.589 to get 0.971.
The mole can be also defined as the number of atoms in exactly 12g of Carbon. In this experiment, the magnesium will be heated and this magnesium will react with the oxygen in the air to form magnesium Oxide. DIAGRAM: METHOD: 1. An empty crucible and its lid were weighed on an electrical balance. The mass of the crucible and its lid were recorded.
c) 0.08 g of oxygen reacted with the magnesium (0.22 g – 0.14 g = 0.08 g). d) Refer to “Determining the Empirical Formula of Magnesium Oxide Lab Solutions” sheet e) Element | % | m (g) | M (g/mol) | n (m÷M) | ÷ by | Ratio | Magnesium | 63.63 | 63.63 | 24.31 | 2.617441382 | 2.273125 | 1 | Oxygen | 36.37 | 36.37 | 16.00 | 2.273125 | 2.273125 | 1 | Since the ratio is 1:1, the empirical formula is MgO. 2. Refer to “Determining the Empirical Formula of Magnesium Oxide Lab Solutions” sheet 3. You need to round the empirical formula to a whole number ratio because you cannot have decimals in the subscripts, which means that you cannot have a fractional amount of molecules in a substance.
The Magnesium strip dissolved in the process and the test tube got hotter. gas test observations: The Hydrogen burned up in the test tube causing a loud pop|The final products were Hydrogen gas and MgCl (a clear/transparent liquid).| |Mg|A shiny opaque metal. -Grey/metallic||| Discussion Questions 1. Identify the reaction in procedure steps 3 and 5 as endothermic or exothermic. Explain why.
During the combustion reaction the ribbon of magnesium metal is heated, it reacts with oxygen from the air in a crucible, producing magnesium oxide: magnesium + oxygen → magnesium oxide We measure the mass of magnesium we use for the reaction, and the mass of magnesium oxide produced at the end of it, then we can work out the mass of oxygen that has been combined with the magnesium. Hypothesis: As we know, the empirical formula of a compound indicates the simplest whole number ratio of atoms of each element present in it. According to Lewis formula of ionic bonding: ionic bonding and the formula of oxidation reaction of Mg: 2Mg + O2 => 2MgO indicates that in one molecule of a magnesium oxide chemical compound there is only one atom of magnesium and one atom of oxygen, therefore by carrying out the experiment the molar ratio of Mg and O is predicted to be 1:1. Method: The materials used in conducting this experiment are as follows: safety goggles, a porcelain crucible with a lid, a length of magnesium ribbon (about 25 cm in length), emery paper, a laboratory balance, a pipeclay triangle, a tripod, a Bunsen burner, and crucible tongs. 1.
Name: Amandeep Sandhu |Date: 06/16/2012 | | |Exp 4: Physical & Chemical Properties |Lab Section: | Data Table: Substance |Color |Odor |Effect of Heat |Cold H2O |Hot H2O |Litmus Test |Dilute HCl |Dilute NaOH | |Mg |Silver Or Gray |Odorless |Forms a white powder |MgO+H2 |Mg(OH2)+H2 |Blue |MgCL2+H2 |MgOH+Na | |Cu | Orange |Odorless |Glows dull red |NO REACTION |Mg(OH2)+H2 |Blue |No Reaction |Cu(OH)2+Na | |Zn | Bluish-white |Odorless |Turns yellow |No Reaction |ZnO+H2 |Blue |ZnCL2+H2 |Na+Zn(OH)2 | |MgO | White |Odorless | |Mg(OH)2) |Mg(OH)2) |Blue |MgCL2+H2O |MgOH+NaO | |CuCO3 | Green |Odorless |Forms Copper Oxide & Carbon dioxide gas |CO2+Ca(OH) 2 |CO2+Ca(OH) 2 |Green |CuCl2+H2CO3 |CuOH+NaCO3 | |Cu(NO3)2 | Blue crystals |Slight | | |Cu2+NO3+H2O |Blue |CuCl2+2HNO3 |CuOh2+NaNO3 | |NaCl |White |Odorless |Melts & become clear liquid | |Na+Cl+H2O |No Color |No Reaction |NaCl+NaOH | | Conclusion: The purpose for this experiment was to combine different chemicals to see if a physical or a chemical change occurred. A physical change happens when the substance changes in appearance yet maintains its physical and chemical properties. A chemical change occurs when a different substance forms with newly formed physical and chemical properties. The first substance was magnesium. Before it was heated, it was a shiny silver strip.
The material is called yellowcake because a drum of the powder produced by early uranium mining operations resembled a yellow cake. However, modern yellowcake usually is brown or black. Photo: A drum of yellowcake uranium, viewed from above. (US Department of Energy) Comments (0)PermalinkShare Chrome Versus Chromium Wednesday May 9, 2012 Have you ever wondered what the difference is between chrome and chromium? Chromium is an element.
The powder that remains will have lost some mass as smoke, but this resultant mass is still more than the mass of the metal that was burnt. Burning magnesium in air is a chemical reaction called oxidation and the compound produced is totally different from the two elements that have been combined. Each element is made up of atoms and the compound is made up of two elements joined together. The chemical formula for the reaction is below; 2Mg + O2 --> 2MgO Magnesium + Oxygen -> Magnesium Oxide The equation above shows that magnesium and oxygen have combined as the product of the reaction, their mass of each element has also combined in the reaction. Magnesium is a very reactive metal which when heated burns with a white flame.