Chemistry Tutorial by University of Arizona Review the basics of chemistry you'll need to know to study biology. Large Molecules by University of Arizona Learn about structures and properties of sugars, lipids, amino acids, and nucleotides, as well as macromolecules including proteins, nucleic acids and polysaccharides.
Containers to hold separated substances Plastic spoons Procedures: For this laboratory you and your group will decide which of the following procedures you will use to separate the mixture you receive. Keep in mind that you may need to repeat some procedures at different stages of the process.
Go ahead and write the procedures below in your notebook now and you can refer to them by number as you use them. Sorting or Manual Separation Substances may differ in this size, shape and color. If the differences are large enough, it may be reasonable to simply pick out one of the substances with a pair of forceps and place it in a separate container.
For example, it would be relatively easy to pick the white jellybeans out of this mixture. Use a magnet to remove certain metals Some substances certain metals are attracted to magnets and others are not. You can use this difference in magnetic properties to separate some mixtures.
If the metal fragments are small, place the magnet in a plastic bag and tie it shut. The baggie covering will make the metal fragments easier to remove from the magnet. Drag the magnet over the mixture to attract magnetic metals.
Brush the attracted metals off the plastic bag into a separate container. Have you ever tried this at the beach? Sand naturally contains iron fragments. In some places you might even be able to find small meteorites. The following procedures require the addition of water to the mixture.
Remember that if you add water, you might be dissolving some of the substances in the mixture. For example, salt or sugar dissolve into water making a solution.
Decanting It is possible to separate some substances based on differences in density. For example, oil floats on top of water.
Add water, allow the substances to separate based on density, and then pour the upper layer with the less dense materials into a separate container. If you have never done it, this video shows the standard way to decant in chemistry direct link. Filtration Filtration takes advantage of differences in particle size to separate mixtures.
Generally filtration in chemistry involves special glassware, such as shown in figure 3. In this lab, we will use a large soda bottle cut in two, with the top inverted into the bottom. Place the filter paper into the top of the soda bottle filter. Pour the liquid to be filtered through the filter.
Larger particles will be trapped in the filter, and the liquid and smaller particles will pass through into the catchment container. Remove the filter and invert into a dish. Scrape off the solids with a spoon, if necessary.
Evaporation Both evaporation and its cousin, distillation, depend on differences in boiling points to separate materials. For example, with a solution of salt and water, the water has a lower boiling point.
When heat is applied, the water boils away and the salt is left behind. It is also possible to leave the solution in the sun for several days. The heat from the sun evaporates the water, again leaving the salt behind.
Evaporation involves applying energy to a solution in the form of heat, usually to remove water from a solution. We will probably not be using evaporation today. Distillation Distillation also takes advantage of differences in boiling point.
A typical laboratory setup for distillation is shown in figure 3.6 EXPERIMENT 2: Separation of the Components of a Mixture Name:_____ Post-Laboratory Questions and Exercises Due after completing the lab.
Answer in the space provided. 1. The Department of Transportation uses a mixture of sand and salt to de-ice roadways in the winter. Homogeneous mixtures are uniform in composition, but heterogeneous mixtures are not uniform in composition.
Air is a homogeneous mixture and oil in water is a heterogeneous mixture. Homogeneous and heterogeneous mixtures can be separated into their components by several physical methods. Introduce students to the concepts of elements, compounds, and mixtures with special emphasis on separating mixtures by filtration and differences in solubility, chromatography, and evaporation.
This page contains a list of cooling bath mixtures.. Table.
Cooling Agent Organic Solvent or Salt T (°C) Notes Dry ice p-Xylene + Mixtures & Solutions Lab Report By Nathan Mitchell 4/23/15 Background Information & Research 1. Paper Chromatography is a method used for the separation of colors which are also referred to as colored chemicals/substances or pigments.
Name: Hour: Lab: Identifying Elements, Compounds, and Mixtures Directions: Read through the review chart below and answer the pre-lab r-bridal.com, rotate through the stations, identifying each substance as an element, compound, or mixture.