Lab 4: Determination of Percent by Mass of the Composition in a Mixture by Gravimetric Analysis Introduction Thermal gravimetric analysis is used to determine the percent by mass is used to determine the percent by mass of a component in a mixture. When a mixture is heated to an appropriately high temperature, one component in the mixture decomposes to form a gaseous compound. The mass of this particular component is related to the mass of the gaseous compound. In this experiment, the percent by mass of sodium hydrogen carbonate (NaHCO3) and potassium chloride (KCl) in a mixture will be determined. Experimental First, we weighed 2 samples, each has 1 gram of NaHCO3-KCl mixture Second, we put the samples in 2 crucibles (A and B) and weighed them.
The reaction that occurred with this step was displacement and metathesis in the form of gas formation. The balanced equation of this step looks as follows: CuSO4aq+Zns→Cus+ZnSO4(aq) Once this step was finished, the remaining copper was retrieved. First, to recover the copper HCl was added to remove all the zinc. When this happened, a yellow tint was observed in the liquid, as well as bubbling as the zinc was broken down. Once the copper dried out, it was weighed and came to a total of 240 mg.
How many grams of CO2 would be liberated by complete thermal decomposition of the MgCO3 in the sample? b) How much would the residue weigh? 3. Describe the location of the hottest portion of a burner flame. The tip of the inner blue flame is the hottest portion.
In this experiment, you will make an experimental determination of the molar volume. The basis of this experiment is the following reaction in which you will react a known mass of magnesium with excess hydrochloric acid to produce the substances shown: Mg(s) + 2HCl(aq) ( MgCl2(aq) + H2 (g) The hydrogen gas is the product that is of interest to you in this experiment. You will make an experimental determination of the number of moles of hydrogen molecules produced and the volume occupied by these molecules. The number of moles of hydrogen will be determined indirectly. The balanced equations for this reaction shows that the molar ratio of magnesium reacted to hydrogen gas produced is 1:1.
Name: Alexis Savastano How Does pH Affect an Enzyme? Catalase is an enzyme that helps decompose the toxic hydrogen peroxide that is produced during normal cell activities. The products of this reaction are water and oxygen gas. The pressure of the oxygen gas in a closed container increases as oxygen is produced. Any increase in the rate of reaction will cause an increase in the pressure of the oxygen.
The mass of the oxygen is resulted from the difference between the masses of product oxide and limiting reagent. In equation 1, the mass of limiting reagent magnesium is found. The mass of the oxide product is determined using equation 2. In equation 3, the amount of oxygen in magnesium oxide is found using the weights of the results found in equation 1 and 2. The mass of the oxygen in the oxide product will represent how much added weight was gained in the reaction.
This is done by a procedure called refluxing. Refluxing is the process of heating a product to the boiling point and re-condensing the vapor continuously. The procedure halogenation is the addition of a halogen to a π bond forming a halo alkane. In this synthetic reaction bromine was used in the process called bromination. The bromine is acting first like an electrophile, and then after bromine has broken the π bond, a carbocation has formed, and a bromide ion has been created, the bromide ion then acts as the nucleophile and forms a bond with the carbocation.
h) A way to make hard water softer is to put an sodium nitrate and create a precipitate to mellow out the reaction. Another way of making it softer is by removing the calcium ions one way of doing that is by boiling the solution to take out some of the ions. Conclusion: Overall, we determined that sodium carbonate, Na2CO3, is the anion that can be used to precipitate the most metal cations. Also, we learned that the anion sodium chloride, NaCl, could be used to remove silver ions from solutions. The stuff that I found interesting was that how many colours you can get when you mix the cations and anions
Computer Additivity of Heats of Reaction: Hess’s Law 18 (1) Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. (2) Solid sodium hydroxide reacts with aqueous hydrochloric acid to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) ) + Cl–(aq) → H2O(l) + Na+(aq) + Cl–(aq) ∆H2 = ? OBJECTIVES • • • • In this experiment, you will Combine equations for two reactions to obtain the equation for a third reaction. Use a calorimeter to measure the temperature change in each of three reactions.
| Chemistry Coursework | How does the concentration of Hydrochloric Acid affect the rate of reaction between Hydrochloric Acid and Sodium Thiosulfate? | | | Initial Planning The aim of my coursework is to investigate the variables that increase the rate of reaction. There are several equations that can be investigated. The main 3 equations are: 1) Hydrochloric Acid + Marble Chips Calcium Chloride + Water +Carbon Dioxide 2HCl (aq) + CaCO3 (s) CaCl2 (aq) + H2O (l) + CO2 (g) 2) Hydrochloric Acid + Magnesium Magnesium Chloride + Hydrogen 2HCl (aq) + Mg (s) MgCl2 (aq) + H2 (g) 3) Hydrochloric Acid + Sodium Thiosulfate Sodium Chloride + Sulfur Dioxide + Sulfur + Water HCl (aq) + Na2S2O3 (aq) NaCl (aq) + SO2 (g) + S (s) + H2O (l) In equation 1, the CO2 produced is monitored over a certain period of time. The more CO2 produced over this time, the higher the rate of reaction.