Separating Mixtures Lab Report

The objective of the experiment “Keeping it Liquid” was to figure out what it takes to keep a compound in a liquid form which caused a phase change. A phase change is when a substance changes from one state or phase to another. There are three main phases that normally occur and they are called Evaporation, Deposition, and Melting. Evaporation is where a liquid changes to a gas. An example of evaporation is when water drops form on the glass of a cold drink on a warm day. Deposition is where a gas vapor goes directly into the solid phase without becoming a liquid first. An example of Deposition often occurs on windows during the winter months. While Melting is where a solid turns into a liquid. Melting occurs when ice turn into a liquid when

There are various techniques to separate a mixture of compounds from each other. One of the commonly used way to isolate compounds from a mixture of two compounds is called extraction. This method of extracting two compounds from each other relies on the different solubility of the compounds in two different solvents.

The purpose of this experiment was to separate the component of three mixtures sand, sodium chloride and calcium carbonate then calculate the percentage by mass of each component recovered from the mixture. The other purpose of this experiment was to show us the students the concepts associated with physical and chemical properties of substances.

21) After all of the solid dissolves, move the flask from the hot plate and allow it cool to room temperature. After a while, crystals should appear in the flask.

The objective of this extraction experiment was to achieve a comprehensive understanding, as well as master the practice, of the technique of separating various individual components of a compound.

After about 1 minute of shaking, the two layers separated. The organic layer on the top layer (consisted of ethyl acetate and naphthalene) collected for further experiment; by adding Sodium Sulfate into organic phase and filtering the Na2So4 from the solution using the wool. The dried organic layer was weighed to get its mass and the residue of Na2SO4 were rinsed with ethyl acetate under vacuum (rotary evaporator). The acid extract on the bottom layer which is a combination of benzoic acid and NaOH were collected in the 50 mL Erlenmeyer beaker for the recovery of acid.

| Can see particles of both. When mixed with water salt dissolves and sand is left.After filter sand is left and salt-water goes through.After evaporations of salt-water, salt is only left in dish.

Because salt dissolves in water, we added water to the salt and sand mixture. Sand is insoluble in water making the sand not dissolve. The mixture containing of sand and salt water was then filtered with filter paper. The filter paper allowed the salt water to pass through because it is a liquid while not allowing sand to pass through because it is a solid. The salt water was then collected in a pre-weighed 250-mL (67.88 gram) beaker while the sand and filter paper was put in a pre-weighed (52.02 gram) 100-mL beaker. The water was then evaporated because we left both beakers to dry overnight.

Someone hands you a container of a mysterious white mixture, and they give you the task to figure out what it is. What would you do to solve the problem at hand? Many scientists might find physical and chemical properties to figure it out. The scientists might look for, odor change, temperature change, fizzing, and bubbling for chemical properties. They also inspect the mixtures for physical properties before a chemical reaction occurs, including shape, size, color, texture, and smell. The Eighth grade thinks that the mystery mixture is C6H8O7(Citric Acid) and NaHCO3(Baking Soda).

10. I then repeated steps 1-9 using alcohol as my solvent, instead of the 1% salt solution.

Based on these results recorded in Figure 1, it appears that Tube 2, which contained the 10% salt concentration, would be one of the optimal concentrations due to its high absorbance similar to Tube 3 and Tube 4 and it having a rate of the reaction was significantly faster than the other tubes. However, taking a deeper look into understanding the information, we can attribute human error to Tube 2. The reason it is believed that Tube 2 contained human error was because the initial recording started with a very high absorbance reading and did not have a large change in absorbance.

11.Pour the mixture mixed with water over the filter paper so that the sand remains on top of the paper and the soluble salt water will go through into the beaker

The next experiment was to test diffusion in agar solution. A petri dish with a layer of solidified agar had four holes punched in it using a No. 5 cork borer. Three holes were punched in a triangle shape with the fourth hole directly in the middle. There should be 15 mm between each outside hole and the middle hole. The three outside holes were filled with one drop each of potassium bromide, potassium Terri cyanide, and sodium chloride. The middle hole was filled with a drop of silver nitrate. It is very important to make sure that none of the holes overflow. After each has been filled allow to sit for an hour and observe the results.

1. Step six in the procedure is necessary because there maybe some left over solution left over in the filter and so we use the water to get rid of that excess solution which is leftover. Step six is also important because this 5 mL of water could make the left over precipitate release excess water in it making it so that the drying process is quicker.

1. Obtain a sample of the mixture. The mixture you will separate contains three components: NaCl, NH4Cl, and SiO2. Their separation will be accomplished by heating the mixture to sub-lime the NH4Cl, extracting the NaCl with water, and drying the remaining SiO2.