Techniques and Measurements
Lab Section: Chem-180
Course Instructor: Purpose
To gain proficiency in determining the volume, mass, length, and temperature of a variety of items using common laboratory measurement devices. In addition, learning how to combine units, determining the density and concentration.
For exercise 1 the experiment was to make measurements using the SI system. First step was to measure different objects lengths; for example CDs, DVDs, spoon, key, and a fork. Then record it on data table in cm, mm, m for all the objects measured. For the temperature measurement experiment, I had to record the temperature with a thermometer of hot tap water and cold tap water. In addition, I had to take the temperature of boiling water using the beaker and the wire gauze burner stand. Then record the information to the data table and then convert it from (°C) to (°F) and (K°).
For the mass experiment, I had to measure a pencil, 5 pennies, 3 quarters, 4 dimes and a key using the scale. First, I had to make an estimated guess of the weight of each object in grams. Then I had to weight each object in order to get the correct weight of the object. After, the actual mass was recorded on the data table; I had to convert the actual mass from grams to kilograms.
For exercise 2 the experiments was to measure volume, density, concentration using the SI system. The experiment to measure volume and density of 5.0 mL distilled water and 5.0 mL of isopropyl alcohol using the scale, graduated cylinder, and short stem pipet. After, getting the mass for both water and isopropyl alcohol, I had to determine the percent error between both liquids, by using the percent error formula and record it on data table.
For exercise 3 the experiment was to create solutions of varying concentrations and densities by diluting a stock solution. The first step was to gather all the equipment needed which, was volumetric flask, distilled water, graduated pipet, pipet bulb, sugar, scale, glass, beaker, cup, and sheet of white paper. Then, I had to weight 8 grams of sugar using the scale. After, I had to determine the number of moles of sugar in the volumetric flask by dividing mass by molecular weight. In addition, I had to place the 8 grams of sugar in the flask. Then fill the flask with distilled water to the 25 mL mark and swirl the volumetric flask until the sugar completely dissolved, afterwards I had to place it on the scale. This exercise helped me determine the final concentration.
Lastly, I had to clean all glassware and put away all lab equipment in a safe area. Observations and Results
Data Table 2: Temperature measurements.
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