What Percent Yield Should Be 100 %?
Ideally, the percent yield should be 100%, as this means that you have recovered 100% of that material. A yield over 100% would mean that the substance still has some traces of another material that is adding additional mass. Ex. The iron filings having some sand particles leftover. A yield under 100% would mean that some of the substance was not recovered, it could have been lost (spilled) or found in another substance (not separated completely). The percent yields may give some insight into what occurred during the procedure. For example if the percent of iron is >100, but the percent of sand is <100 then it may show that some sand was not separated from the iron, and was measured with that material.
The tare button on the balances will …show more content…
“zero” them. It will show a value of zero even if there is weight on the scale and will then show the weight of the substance added post-tare. It can be used to measure materials as they are added to a container by “taring” after adding each new material. It is useful to get the weight of a material without having to subtract the weight of the container.
Some materials were larger or smaller so the larger ones could be sifted out while the smaller materials fell through. The beads had a low density and in turn floated in water while the rocks were of a high density and sunk. This allows for the beads to be skimmed off the top of the water; leaving the rocks on the bottom. The iron filings are magnetic but the salt and sand was not. This aided in separating the iron by using a magnet to lift the iron from the mixture. The sand is not water soluble and the salt is. Due to this we added water to the sand and salt and dissolved the salt in the water.
Some issues that occurred during the lab were that when the magnet was used to separate the iron filings some sand and salt also remained with the iron.
Also since the iron was a powdery substance some still remained in the sand/salt mixture. This may raise or lower the recovered mass depending on how thorough the group was is separating out the iron. Or it may balance out leaving a almost 100% recovery percent. This may also raise the salt or sand recovery percent due to the leftover iron. Because the salt was dissolved into water anything that was moistened by the water would leave a salt residue when dried. This was noticed on the sand as white dust. This will lower the salt recovery but raise the sand recovery.
If there is “extra” product this may be some of the other materials from the mixture that wasn’t separated, such as iron or salt. This can be as the separation techniques used aren’t perfect and won’t extract 100% of the material in some cases.
The missing salt could be lost as not all the water/salt mixture was poured into the flask. Some was left behind in the flask used in filtration and some was left in the sand.
One heterogeneous mixture was the the rocks and beads. The distinct shape and colouration of the beads as well as the large size of both materials made it easy to distinguish them.
One heterogeneous mixture was the water and salt. As it looked just like water( no salt granules).
The iron filings was a pure substance as it isn’t a mixture. It is just
the element iron.
The salt ended up as a white powder on the inside walls of the flask.
To separate the iron, salt, sand and rocks we took advantage of their physical and chemical properties. The physical property of size allowed us to separate the rocks from the other substances as the rocks were too big to fall through the small holes in the metal strainer, while the small sand, salt, and iron fell into the cup below. Then we used the chemical property of magnetism to separate the iron. The iron filings are magnetic while the sand and salt is not. We used this to separate out the iron by using a magnet to lift the iron while leaving behind the sand and salt. Again using a chemical property of the salt, we were able to extract the sand. The salt is water soluble, so it dissolves in water, and the sand is not. By adding water we were able to create sand and saltwater. Also by using the physical property of size we used a filter to separate the sand from the salt water.
The tare button on the balances will …show more content…
“zero” them. It will show a value of zero even if there is weight on the scale and will then show the weight of the substance added post-tare. It can be used to measure materials as they are added to a container by “taring” after adding each new material. It is useful to get the weight of a material without having to subtract the weight of the container.
Some materials were larger or smaller so the larger ones could be sifted out while the smaller materials fell through. The beads had a low density and in turn floated in water while the rocks were of a high density and sunk. This allows for the beads to be skimmed off the top of the water; leaving the rocks on the bottom. The iron filings are magnetic but the salt and sand was not. This aided in separating the iron by using a magnet to lift the iron from the mixture. The sand is not water soluble and the salt is. Due to this we added water to the sand and salt and dissolved the salt in the water.
Some issues that occurred during the lab were that when the magnet was used to separate the iron filings some sand and salt also remained with the iron.
Also since the iron was a powdery substance some still remained in the sand/salt mixture. This may raise or lower the recovered mass depending on how thorough the group was is separating out the iron. Or it may balance out leaving a almost 100% recovery percent. This may also raise the salt or sand recovery percent due to the leftover iron. Because the salt was dissolved into water anything that was moistened by the water would leave a salt residue when dried. This was noticed on the sand as white dust. This will lower the salt recovery but raise the sand recovery.
If there is “extra” product this may be some of the other materials from the mixture that wasn’t separated, such as iron or salt. This can be as the separation techniques used aren’t perfect and won’t extract 100% of the material in some cases.
The missing salt could be lost as not all the water/salt mixture was poured into the flask. Some was left behind in the flask used in filtration and some was left in the sand.
One heterogeneous mixture was the the rocks and beads. The distinct shape and colouration of the beads as well as the large size of both materials made it easy to distinguish them.
One heterogeneous mixture was the water and salt. As it looked just like water( no salt granules).
The iron filings was a pure substance as it isn’t a mixture. It is just
the element iron.
The salt ended up as a white powder on the inside walls of the flask.
To separate the iron, salt, sand and rocks we took advantage of their physical and chemical properties. The physical property of size allowed us to separate the rocks from the other substances as the rocks were too big to fall through the small holes in the metal strainer, while the small sand, salt, and iron fell into the cup below. Then we used the chemical property of magnetism to separate the iron. The iron filings are magnetic while the sand and salt is not. We used this to separate out the iron by using a magnet to lift the iron while leaving behind the sand and salt. Again using a chemical property of the salt, we were able to extract the sand. The salt is water soluble, so it dissolves in water, and the sand is not. By adding water we were able to create sand and saltwater. Also by using the physical property of size we used a filter to separate the sand from the salt water.