Identify data sources, plan, choose equipment and perform a firsthand Investigation to separate the components of a naturally occurring mixture such as sand, salt and water. 8. 2. C Gather firsthand information by carrying out a gravimetric analysis of a mixture to estimate Its percentage composition. Aim: To conduct a gravimetric analysis in order to determine the composition percentage of the initial mixture of carbon and sodium chloride.
Hypothesis: the mixture will be composed of a higher percentage of carbon than sodium chloride. Materials g of sodium chloride and carbon mixture. Lax Erlenmeyer flask Lax Tripod Lax Bunsen burner Lax clay triangle Lax evaporating basin Lax sheet of filter paper Lax surging rod Lax Beaker Lax funnel xx porcelain chips Lax scale Risk Analysis Hazard Risk Risk Minimization Spill Hazard Slippage on the spillage Leather shoes, good soles that provide traction.
Heat Hazard Burns Hair tied back using correct Bunsen lighting procedure shatter Hazard Cuts on broken glass/porcelain Leather shoes that protect feet from broken glass on the floor Method: then added to the beaker and stirred with the stirring rod in order to dissolve the alt. 3. The solution was then filtered through the previously weighed filter paper, using a funnel, into an Erlenmeyer flask, in order to separate the insoluble carbon from the sodium chloride solution. 4.
The remaining sodium chloride was then poured into the also previously weighed evaporating basin with the two porcelain chips, and placed atop a beaker and clay triangle. 5. Heat was then added by a Bunsen burner to evaporate the water, leaving the remaining sodium chloride in the evaporating basin. 6. The evaporating basin was then weighed with the sodium chloride in it. Diagram: Results: Substance/ObJect Initial Mass (g) Final Mass – after separation (g) Mixture 2. 0 Carbon 0. 66 Sodium Chloride 1. 00 Filter Paper 1 . 45 Evaporating Basin 48. 20 49. 20 Discussion Questions 1 .
Calculate the % concentration by mass of the two components in the mixture. E. G. % sodium chloride = 100 x mass of sodium chloride in evaporating basin / mass of original mixture. Sodium chloride = 1. 0/2. 0 = 100 x 66/200 2. Does your result in (1) add up to 100%? Account for any missing components of the mixture. No, it doesn’t. There are three main places in the experiment where monuments could’ve been lost. Carbon could’ve been lost when the solution was filter through the filter paper to the Erlenmeyer flask, as there could’ve been residual carbon left in the beaker that didn’t go through the filter paper.
Mass also could’ve been lost when the sodium chloride solution was transferred from the Erlenmeyer flask into the evaporating basin, as there is the potential that not all of the solution made it into the basin, resulting in the loss of mass. The final occurrence is when the sodium chloride solution was incorrectly overheated while it was being evaporated ND the mixture began to bubble and explosive evaporation occurred, resulting in the potential loss of some sodium chloride. 3. A better experimental method would involve “heating the evaporating basin to constant mass” before weighing it.
This procedure involves repeated cycles of heating, cooling and weighing until the mass obtained no longer changes. Suggest a reason why this would increase the accuracy of your mass of sodium chloride. The addition of energy to a substance results in a change in its physical structure. Although small, the change heat has on most substances is to cause expansion and his means that the mass is thence changed. Because the basin was not heated to a constant mass prior to the addition of the solution, it was during the evaporation of the solution.
Meaning the results were somewhat skewed by the fact that the mass of the basin changed during the evaporation, meaning there was probably less salt in the basin than the results displayed. 4. Construct a flowchart detailing the separating methods used in this experiment. Carbon (s) and Sodium Chloride (s) aqueous mixture Filtration, resulting in the separation of carbon Sodium Chloride solution (as) Evaporation 5. Identify the physical property used by each separating method (e. G. He process of decanting relies on the physical property of density) The two properties were solubility and particle size. The fact that the sodium chloride was soluble and the carbon was not, resulted in it being added to water, then the fact that the carbon was a larger particle was used to filter it out using the filter paper and funnel. Conclusion: A gravimetric analysis was conducted and it was determined that, contrary to the hypothesis, in the sodium chloride and carbon mixture, there was a higher concentration of sodium chloride than carbon.