Intro In this lab, we will create a chemical reaction between the reactants oxygen (O2) and magnesium (Mg) using combustion. The product will be magnesium oxide (MgO). In this lab we will record the masses of reactants and products to perform stoichiometry of the chemical equation Mg + O2 -> MgO. The actual yield of product will differ from the theoretical yield based on how the experiment is performed. The independent variable is the product amounts and the dependent variable is the percent yield. Literature Review The word stoichiometry originates from the Greek language (ChemTeam). The Greek words for “element” and “measure,” stoicheion and metron, are what combine together to make that word stoichiometry. When performing stoichiometry, the masses of products and the masses of reactants involved in the particular chemical equation you are observing are used in the calculations. The first person to record the concept of stoichiometry was Jeremias Benjaim Richter, a German chemist. He said, originally in German and translated to English, “Stoichiometry is the science of measuring the quantitative proportions or mass ratios in which chemical elements stand to one another.” In a typical stoichiometry problem, you will be given the chemical equation of a reaction, a certain amount of reactant, and then you will need to find how much of the product can be formed. The skills needed to complete a stoichiometry problem are balancing equations, converting between grams
Stoichiometry: A branch of chemistry that deals with the relative quantities of reactants and products in chemical reactions.
The purpose of this experiment is to distinguish the relationships between reactants and products, in addition to expanding on concepts such as single displacement reactions, mole ratio values, moles to mass, theoretical yields, limiting reactants, excess, stoichiometric relationships and percentage errors.
Stoichiometry is a very important part of chemistry. Stoichiometry refers to calculating the masses of molecules and their products . The reactants are usually given and stoichiometry is used to find the products of the equations as well balancing the equation. An example of this would be sodium chloride (NaCl). Stoichiometry will say that if there are ten thousand atoms of sodium and one atom of chlorine, only one molecule of sodium chloride can be made and that fact can never be changed.
Purpose: To determine the percent magnesium by mass in magnesium oxide and to observe if the percentage composition is constant by comparing class results.
The aim of the lab was to determine the molar enthalpy of the combustion of magnesium using values from reactions between magnesium and magnesium oxide in hydrochloric acid solution using Hess’s Law and Calorimetry. The calculated molar enthalpy of the combustion of magnesium from this experiment was -633.6KJ/mol. This result was found by putting a known mass of magnesium metal as well as magnesium oxide powder into a concentration of HCl. Firstly, a styrofoam calorimeter was used to determine the standard reaction temperature of magnesium metal and hydrochloric acid. Next, calorimetry was again used to determine the reaction temperature of magnesium oxide and hydrochloric acid. Lastly, the thermochemical equations for the two
Stoichiometry is a method scientists use to presume how two or more substances will react together. In order to do so successfully, the reactants are positioned on the left and the products on the right. The most important part of successfully
The purpose of this lab was to test the law of definite proportions for the synthesis reaction of combusting magnesium. In this lab, the polished magnesium ribbon was placed in covered crucible and was heated in order for it to react with Oxygen presented in air and in water provided. The result showed that Magnesium oxide formed through chemical reaction was made up of 60.19% magnesium and 39.81% oxygen, which is approximate proportion of both particles in every Magnesium oxide compound. From this lab it can be concluded that the law of definite proportion stating that the elements in a pure compound combine in definite proportion to each other is factual.
The purpose of this experiment is to verify the formula of magnesium oxide based on the masses of magnesium and the product (MgO). We verify the formula firstly by calculating the empirical formula of magnesium oxide and then calculating creating the magnesium oxide itself- a magnesium ribbon is combined with oxygen in the presence of air through combustion and this forms MgO. The empirical formula of a compound is the simplest method of expressing a chemical formula in whole-number ratios of the constituent atoms that are consistent with masses measured in the experiment; whereas the molecular formula expresses the chemical formula using the actual number of atoms. For example, the molecular formula of anthracene is C14H10 while the empirical formula is C7H5.
The first experiment is about the combustion of magnesium after which the ash is formed.
In a chemical reaction, atoms may be rearranged according to their position, but as the law of conservation of mass states, atoms are never created nor destroyed during a reaction. In Chemistry, Stoichiometry can be defined as the observation of the amount of substances used during a reaction. In a reaction a certain number of reactants form a particular amount of product. In the above experiment, the goal was to react copper chloride with sodium phosphate to form Copper (II) phosphate trihydrate. When a chemical reaction is performed in a laboratory, the ratio of the number of reactants used for the reaction is not equal to the stoichiometric ratio of the reaction.
I could use a gas syringe to collect the gas that will evolve from my
) Suppose that some magnesium oxide smoke had escaped during the investigation, the Mg:O ratio would have increased from 58% to 72%. The final mass of MgO would have decreased because the magnesium oxide smoke is part of the product and when some of it escapes, it decreases the final mass.
In this lab, a calorimeter was used to find the enthalpy of reaction for two reactions, the first was between magnesium and 1 molar hydrochloric acid, and the second was between magnesium oxide and 1 molar hydrochloric acid. After the enthalpy for both of these were found, Hess’ law was used to find the molar enthalpy of combustion of magnesium, using the enthalpies for the two previous reactions and the enthalpy of formation for water. The enthalpy of reaction for the magnesium + hydrochloric acid reaction was found to be -812.76 kJ. The enthalpy of reaction for the magnesium oxide + hydrochloric acid reaction was found to be -111.06 kJ. These two enthalpies and the enthalpy of formation for water were manipulated and added together using Hess’s law to get the molar enthalpy of combustion of magnesium. It was found that the molar enthalpy of combustion of magnesium was -987.5 kJ/mol. The accepted enthalpy was -601.6 kJ/mol, which means that there is a percent difference of 64%. This percent difference is very high which indicates that this type of experiment is very inefficient for finding the molar enthalpy of combustion of magnesium. Most likely, a there are many errors in this simple calorimeter experiment that make it inefficient for finding the molar enthalpy of combustion of magnesium.
The purpose of this lab was to test the law of conservation of mass by comparing the total mass of the reactants in a chemical reaction with the total mass of the product.
The term concentration refers to the amount of a substance present in a certain volume of liquid or gas. Increasing the concentration of the reactants will increase the rate of the reaction. If the concentration of a reactant in a solution is increased, there will be a greater number of particles in a given volume of solution. This means the particles are more likely to collide and therefore react when there are more of them. Collisions between particles are necessary for the reactants to rearrange and form the products. In this experiment, the rate of the reaction between magnesium ribbon and hydrochloric acid will be increased by adding a higher concentration of hydrochloric acid each time. The chemical equation between magnesium ribbon and hydrochloric acid can be written as: