p. 51-52, #25-34

25. Qualitative tests are tests that test for the presence or absence of a particular substance in a sample. Quantitative tests do the opposite, determining the amount of a specific substance present in a sample.
26. A confirming test is a positive test that confirms if an ion in question is present in a sample.
27.
a. the reference solution: The point of having a reference solution is to have a sample with the known ion to be compared to the samples that we are questioning for having the ion.
b. the distilled-water blank: We use a distilled-water blank as another sample to compare to because we know that the distilled-water does not have any ions.
28. No, the student should not automatically assume that no iron is present in the sample because over time due to oxidization, iron changes color. Eventually, color may appear in the sample.
29.
a. I would use the steps from the previous lab: oil-water separation, sand filtration, and charcoal adsorption/filtration
b. Oil-water separation helps in showing us if it is a suspension because it removes the oil particles, and once the oil is removed it makes the particles more visible. By even having to do this procedure, we automatically know that it is a suspension because it contains oil particles. Sand filtration determines whether the foul water is a suspension or a colloid/solution. Once the water has been filtered through the sand, and the water is clear with barely any particles, we know that the water is a suspension. If there are still some small particles and color, we know that it is a colloid/solution because the particles were too small to be removed by the sand. Finally, charcoal adsorption will give the end result of whether the liquid is a colloid or a suspension because after the procedure is done, the Tyndall effect will either show that there are particles or that there are not (solution).
30. If you do not shake before using a medicine that directs you to do so, you are not allowing the suspension to mix properly. You may only be ingesting certain parts of the liquid, leaving some vital particles that are needed for the medicine to work at the bottom of the bottle. Also, if you take the medicine for a prolonged period of time without shaking it and then when it reaches the end of the bottle, you are putting yourself at risk for an overdose of the medication. This is so because the particles have caked at the bottom of the container, and the medicine you are taking is much more concentrated now.
31. It is useful for the element symbols to have international acceptance so that elements don't get mixed up, potentially causing a dangerous reaction. While working in a lab, you may have people from all over the world and everyone needs to be working with the same understanding of the elements and chemicals that they are experimenting with.
32. On paper
33. No, it is not possible because even water that is purified becomes contaminated by atmospheric gases in the air such as nitrogen, oxygen, and carbon dioxide.
34. H20 is a liquid, while hydrogen and oxygen are both gasses. Hydrogen needs one more electron to be stable and have a complete shell and oxygen needs two more electrons. Oxygen is also much more magnetic than hydrogen.