Mixture Separation Lab Submitted by: Owen Raymond Partner: Mason Haze October 9, 2015 Chemistry Period 3
Separating the Components of a Mixture
Objective: In this lab the components of a mixture are trying to be separated from one another through the use of separation techniques. This lab also helps to gain more understanding of physical intensive properties, mixtures, and separation techniques.
Introduction: This lab helps to gain a basic understanding of separation techniques. An understanding of what mixtures, physical intensive properties, and separation are required for this lab. A good understanding of this lab is important because similar processes can be used when trying to clean oil spills, create clean water, or solve other environmental problems. A mixture is a physical combination of substances. Air and soda are two example of mixtures. There are two types of mixtures, heterogeneous and homogeneous. A heterogeneous mixture is a mixture that is not uniform throughout and has visibly different components. An example of this would be oil and water. A homogeneous mixture is a mixture that is uniform, the same, throughout. Homogeneous mixtures are also called solutions. An example of this would be salt and water. Physical intensive properties are a type of physical property. Unlike extensive properties, intensive properties are not reliant on the amount of substance there is. Physical
intensive properties depend on only the identity or nature of the substance, no matter how much there is it will always stay the same. Some examples of physical intensive properties are malleability, boiling points, and magnetization. Separation techniques are techniques used to separate the components of a mixture. Some of the separation techniques used include evaporation, magnetism, and filtering. Evaporation is a method that is used when trying to separate a solute from a solvent. During evaporation the liquid is allowed to evaporate until only the solute is left behind. The solid gets left behind because it is not capable of evaporating. Magnetism uses a substance’s magnetic properties to separate it from a mixture. Filtering is a method that is used when trying to separate a solid from a mixture of liquids. Filtration captures the solid and lets the liquid run and drain out. This can be done by using filter paper, which captures solids because they are not capable of passing through the pores of the filter paper. These terms relate because separation techniques are used to separate mixtures, and the properties of substances that allow and cause them to be separated are intensive properties.
Materials:
Weight boats 2 pieces of filter paper Beaker Funnel Erlenmeyer Flask Premade mixture Hotplate Electronic balance Magnet Ice Water Goggles Lab aprons
Procedure:
1. Mass weight boat 2. Use magnet to pick up iron fillings in mixture 3. Place fillings into weight boat 4. Mass weight boat with iron fillings 5. Add 25ml of water at 40C into beaker 6. Place mixture into beaker and add water 7. Mix mixture with heat until the salt and potassium nitrate are dissolved 8. Mass filter paper 9. Filter mixture 10. Allow sand and filter paper to dry 11. Mass filter paper and sand 12. Cool mixture down to below 20C and wait until potassium nitrate recrystallizes 13. Mass filter paper 14. Filter solution 15. Allow filter paper and potassium nitrate to dry 16. Mass filter paper 17. Mass beaker 18. Pour solution into beaker 19. Evaporate water 20. Mass beaker and salt Data:
Mass of
Iron
Sand
Salt
Potassium
2.19g
0.87g
135.40g
Nitrate 0.84g
5.02g
8.45g
149.56g
2.00g
Container/Holde r (In grams) Mass of Container/Holde r with Substance (In grams) Calculations: Mass Calculations Iron
Sand
Salt
5.02g – 2.19g = 2.83g
8.45g – 0.87g = 7.58g
149.56g – 135.40g = 14.6g
Potassium Nitrate 2.00g – 0.84g = 1.16g Percent Error Calculations Iron
Sand
2.68g – 2.83g x 100 = 5.59% 2.68g
7.55g – 7.58g x 100 = 0.397% 7.55g
Salt
Potassium Nitrate
9.38g – 14.16g x 100 = 50.9% 9.38g
3.79g – 1.16g x 100 = 69.3% 3.79
Conclusion: Claim: The separation techniques used to separate the components of the mixture were successful. Evidence: In the lab the mass of the iron fillings that were obtained was 2.83g. The actual amount that should have been there was 2.68g. This means that the percent error was 5.59%. The mass of the sand that was obtained was 7.58g. The mass that it should have been was 7.55g. This means that the percent error was only 0.397%. The mass of the salt that was obtained was 14.6g. The mass that it should have been was 9.38g. This means that the percent error was 50.9%. The mass of the potassium nitrate that was obtained was 1.16g. The mass should have been 3.79g. This means that the percent error was 69.3%. Reasoning: When separating the iron from the mixture the magnetic properties of the iron were taken advantage of and magnetization was used. Filtration was used when separating the sand from the solution. This was successful because the sand was captured in the filter paper while the
dissolved salt and potassium nitrate passed thought. Filtration was also used when separating the potassium nitrate from the mixture. However, the potassium nitrate had to be recrystallized before it was filtered, which may have led to an error in the lab. Evaporation was used when separating the salt from the mixture. This was done by simply evaporating the remaining water, and then measuring the salt that was left behind. The salt was left behind because it has a higher mass than water and is not capable of evaporating. The separation techniques are known to have been successful because both the iron fillings and the sand were within a 10% error range. This means that they were accurate and were precise with the true amounts. The separation techniques worked even though the salt and potassium nitrate percent errors were not within 10% because there was probably an error in the recrystallization process for the potassium nitrate. Not all of the potassium nitrate recrystallized and was able to be filtered out, thus leaving the salt mass to be too high, and the potassium nitrate mass to be too small. Rebuttal: Some say that the separation techniques did not work. This may be because there was an error in the lab. There may have been some other materials mixed in with the iron. All of the sand may not have been captured by the filter paper. The recrystallization process for the potassium nitrate may have had an error or may not have been completed. Any of these factors would cause the percent errors to be higher and some to think that the separation techniques were invalid. Even, though the salt and potassium nitrate may have been off of their true amounts, it is not the separation techniques that caused this to happen. The recrystallization process is what would have caused the amounts to be off, not the separation techniques.
Reflection: In this lab there may have been error during the recrystallization process of the potassium nitrate. The potassium nitrate may not have been completely recrystallized or may
have dissolved in the water when it was being filtered. Both of these situations would then cause the mass of the obtained salt to increase and the mass of the obtained potassium nitrate to decrease and then cause the percent errors to increase.
