Lab 1-3 Separating a mixture

In this experimented, the mixture I created was 30% sand, 30% iron, and 40% salt. Right away, it was easy to determine how to separate the homogeneous solution; use a magnet to remove the iron, dissolve the salt in the remaining solution in water, drain the salt water and filter the sand, and finally, boil the salt water to get the solid salt back.
When separating the mixture, there was obviously some room for error. Iron, which was the easiest to separate, had a small percent error, but I was unable to remove all of it, thus, it had 5.47% less than the amount I started with. Sand, on the other hand, was a little harder to separate from the salt water, but when I drained it, it must have still been semi-saturated, for it had more mass after being separated from the solution. As for salt, 'twas very difficult scraping it off the inside of the beaker once boiling out the water. Because of this, there was a very large percent error in the salt category.
To better the process of the separation, I could have let the sand filter out for a longer time. If I had made sure that all of the water was out of the the sand, i would have gotten a better measurement of how much sand I was able to recover.
If after doing the math, there was a non-terminating decimal, I rounded the answer to the hundredths. If the answer did not, I rounded to the tenths.
This related to what we have been doing in class, because we are learning about homogeneous and heterogeneous mixtures, and how they can be changed. We have also been learning about the balance of matter, and how it cannot be destroyed. Thus, we needed to determine what happened to the part of the substances that we did not recover, and where they could have gone.
When manufacturing and purifying a chemical, companies will take other factors into consideration, such as bacteria, foreign minerals, and the pH of the substance. If the pH is balanced to whet it should be, then that indicates that the purification is probably complete. If not, then some more purification needs to be done.