Sand Practical

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If this practical was to be repeated I would aim to achieve more accurate results with a lower margin error. I would attain this by not repeating the mistakes made in this instance of this practical, which mainly includes the handling of sand. Doing repeats is a method to improve the accuracy of results because it is a mixture the final results can vary based on the sample collected. If multiple repeats were conducted, it is possible to have a more accurate result as each sample collected from a mixture can have difference ratios of components. Another way the experiment can be improved is a better sample of the mixture was obtained; the mixture that we had collected consisted of much more liquid making our final ratio of sand:shells:salt:water approximately 2.5:1:30:67 whereas is we had taken a difference sample with less liquid and more sand then the ratio can drastically change.

Questions:

- Evaporation was used as the basis of separation as the boiling point of water is 100˚C while the boiling point of salt is much higher.

- The salt that has been isolated is a mixture, although it would be close to a pure substance but due to the fact that this is a sample of beach sand there could very well be traces of other minerals or metals within the salt which would not have evaporated.

- Gravitational separation can be useful as it allows chemist to separate mixtures which cannot use the before mentioned separation techniques due to their physical properties being too similar. Two situations where this could be used is in agriculture where a farmer would want to remove impurities from a crop or a geologist could use it to isolate certain metals or ores found.

- A) Sieving can be used in mining if you are searching for a mineral/ore in water as water passes through the small holes.

B) Sedimentation is mainly used in the process of treating water into drinkable water. It is one of the first steps as it separates the larger solids from the liquid.

C) Evaporation is used in the natural process of salt farming, the water containing salt evaporates leaving salt.

D) Distillation is used in the alcohol industry in order to create distilled drinks containing a much higher percentage of alcohol

E) Fractional is used in the separation of petroleum as crude oil have different properties when heated to different temperatures such as lubricating oil, heating oil, kerosene, gasoline and petroleum gas.

- Iron ore: 34.5%

Copper: 15.2%

Silicon: 50.3%