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I. Title ? Chapter 5 Lab Test
II. Purpose ? To successfully separate the substances in the “sludge” and to identify their characteristic properties.
III. Methods and Materials ?
A. safety goggles, matches, alcohol burner/burner stand, test tubes w/ rubber stoppers, thermometer, pegboard, water, bucket, rubber band, calculator, sludge, rock salt, moth flakes, porcelain chips, sugar, salt, filter paper, funnel, test tube holder, paper towels, evaporating dish, rubber tubing, graduated cylinder
B. We filtered a sample of the sludge to separate the solid from the liquid. It smelled of alcohol. Next, we attempted to use fractional distillation in order to find out how many liquids we had present. When we made our test graph, there was only one plateau so we concluded that there was only one substance present. We then found three characteristic properties: density, odor, and flammability. We labeled this substance liquid 1. Next, we filtered all of our sludge by pouring through a funnel into a test tube. We were then left with the liquid in a test tube and the solid substances on the filter paper. We then used mechanical separation to separate the larger chunks of solid from the smaller/powdery solids. We then found the characteristic properties of solubility, appearance, and odor of the larger chunks. We found the odor of moth flakes and rock salt to help us decide which substance we were dealing with. We labeled this substance solid 2. Next, we took a sample of the smaller/powdery substance and heated it in an evaporating dish over an alcohol burner. We were left with a light brown liquid that solidified as it cooled and had a faint caramel odor. We took a sample of pure sugar from the cart and heated it in an evaporating dish over an alcohol burner. We were left with a brown liquid that solidified as it cooled and smelled of caramel. We decided that we had two substances and that one of them had the characteristic properties of sugar. We turned in our three substances: Liquid 1, Solid 2, and a third mixture of 2 unseparated solids.
IV. Data and Observations ?Data for Test Graph:
Time (min.) Temperature (?C)0 21
A. The liquid we separated from the solid was clear in appearance. During fractional distillation, the liquid bubbled while boiling and was soon all boiled away. When testing the liquid for flammability, the Stirring rod dipped in the liquid ignited when held over an open flame. After filtering the rest of our sludge, the liquid appeared transparent and the solid appeared white in color and contained large and small chunks of solid. The large chunks of solid that were mechanically separated did dissolve when mixed with water. The large chunks appeared for the most part transparent but partly cloudy. The odor of the moth flakes did not match the odor of our solid 2 and the odor of the rock salt did match the odor of solid 2. When we took a sample of the smaller/powdery substance and heated it in an evaporating dish over an alcohol burner we were left with a light brown liquid that solidified as it cooled and had a faint caramel odor. When we took a sample of pure sugar from the cart and heated it in an evaporating dish over an alcohol burner we were left with a dark brown liquid that solidified as it cooled and smelled of caramel.
B. Characteristic Properties ?
? Liquid 1- Density: .79 g/cm3Flammability: YesOdor: alcohol
? Solid 2- Solubility: YesAppearance: mostly clear, but partly cloudyOdor: none
V. Calculations ? Density of Liquid 1:
VI. Results and Conclusions ?A. The two methods that we used to help separate our sludge worked because they helped us to successfully separate two substances from our sludge.B. We conclude that Liquid 1 has a density of .79g/cm3, is flammable, and smells of alcohol. We conclude that Solid 2 has no odor, appears clear and chunky, and is soluble in water.C. We have decided, based on our data, that Liquid 1 is isopropyl alcohol; Solid 2 is rock salt; Solid 3 is sugar; and solid 4 is salt.
VII. Graphs – (Next pages)
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